SlideShare a Scribd company logo

Capitol js

•
•
Brendan Eich
Brendan Eich

The document discusses the history and goals of JavaScript and the Harmony project. It provides a brief overview of JavaScript's origins and evolution from 1995 to the present. It then outlines the main goals of the Harmony project, which aims to create a better language for complex applications, libraries, and code generators. The document proceeds to summarize features that have been approved for inclusion in ES6, such as let/const block scoping, destructuring, default parameters, and iterators/generators. It also discusses other proposals under consideration, such as binary data types and quasi-literals for safer string interpolation.

TechnologyNews & Politics
1 of 118
Download to read offline
Capital^H^HolJS brendan@mozilla.org Sunday, September 18, 2011
Capital^H^HolJS brendan@mozilla.org • History, goals Sunday, September 18, 2011
Capital^H^HolJS brendan@mozilla.org • History, goals • ES6, what’s in it? Sunday, September 18, 2011
Capital^H^HolJS brendan@mozilla.org • History, goals • ES6, what’s in it? • Dart: I can’t wait! Sunday, September 18, 2011
Capital^H^HolJS brendan@mozilla.org • History, goals • ES6, what’s in it? • Dart: I can’t wait! • Harmony tune-up Sunday, September 18, 2011
Capital^H^HolJS brendan@mozilla.org • History, goals • ES6, what’s in it? • Dart: I can’t wait! • Harmony tune-up • RiverTrail demo Sunday, September 18, 2011
A very brief history mozilla 2 Sunday, September 18, 2011
A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java mozilla 2 Sunday, September 18, 2011
A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) mozilla 2 Sunday, September 18, 2011
A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) mozilla 2 Sunday, September 18, 2011
A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk mozilla 2 Sunday, September 18, 2011
A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk • 1999: ES3: function expressions, RegExps, try/catch/finally, switch, do-while mozilla 2 Sunday, September 18, 2011
A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk • 1999: ES3: function expressions, RegExps, try/catch/finally, switch, do-while • 2005: the Ajax revolution, followed by “The Ajax Experience” mozilla 2 Sunday, September 18, 2011
A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk • 1999: ES3: function expressions, RegExps, try/catch/finally, switch, do-while • 2005: the Ajax revolution, followed by “The Ajax Experience” • 2008: ES4 RIP, Harmony founded in July at the Oslo TC39 meeting mozilla 2 Sunday, September 18, 2011
A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk • 1999: ES3: function expressions, RegExps, try/catch/finally, switch, do-while • 2005: the Ajax revolution, followed by “The Ajax Experience” • 2008: ES4 RIP, Harmony founded in July at the Oslo TC39 meeting mozilla • 2009: ES5: “use strict”, JSON, Object.create, etc. 2 Sunday, September 18, 2011
The Harmony goals mozilla 3 Sunday, September 18, 2011
The Harmony goals • Be a better language for writing: mozilla 3 Sunday, September 18, 2011
The Harmony goals • Be a better language for writing: • complex applications mozilla 3 Sunday, September 18, 2011
The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications mozilla 3 Sunday, September 18, 2011
The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition mozilla 3 Sunday, September 18, 2011
The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition • Better tests, if not a testable (executable) specification mozilla 3 Sunday, September 18, 2011
The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition • Better tests, if not a testable (executable) specification • Adopt de facto standards where possible mozilla 3 Sunday, September 18, 2011
The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition • Better tests, if not a testable (executable) specification • Adopt de facto standards where possible • Keep versioning as simple and linear as possible mozilla 3 Sunday, September 18, 2011
The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition • Better tests, if not a testable (executable) specification • Adopt de facto standards where possible • Keep versioning as simple and linear as possible • Support a statically verifiable, object-capability secure subset mozilla 3 Sunday, September 18, 2011
Approved for ES6 mozilla 4 Sunday, September 18, 2011
Approved for ES6 • let, const, function in block scope mozilla 4 Sunday, September 18, 2011
Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() mozilla 4 Sunday, September 18, 2011
Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} mozilla 4 Sunday, September 18, 2011
Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) mozilla 4 Sunday, September 18, 2011
Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) • proxies, weak maps: Proxy.create(handler, proto), new WeakMap mozilla 4 Sunday, September 18, 2011
Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) • proxies, weak maps: Proxy.create(handler, proto), new WeakMap • modules: module M { export function fast_sin(x) {...} } mozilla 4 Sunday, September 18, 2011
Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) • proxies, weak maps: Proxy.create(handler, proto), new WeakMap • modules: module M { export function fast_sin(x) {...} } • iterators, generators: function* gen() { yield 1; yield 2; } mozilla 4 Sunday, September 18, 2011
Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) • proxies, weak maps: Proxy.create(handler, proto), new WeakMap • modules: module M { export function fast_sin(x) {...} } • iterators, generators: function* gen() { yield 1; yield 2; } mozilla • comprehensions: return [a+b for a of A for b of B] 4 Sunday, September 18, 2011
Yet more approved for ES6 mozilla 5 Sunday, September 18, 2011
Yet more approved for ES6 • Binary data: mozilla 5 Sunday, September 18, 2011
Yet more approved for ES6 • Binary data: • const Point2D = new StructType({ x: uint32, y: uint32 }), Color = new StructType({ r: uint8, g: uint8, b: uint8 }), Pixel = new StructType({ point: Point2D, color: Color }); mozilla 5 Sunday, September 18, 2011
Yet more approved for ES6 • Binary data: • const Point2D = new StructType({ x: uint32, y: uint32 }), Color = new StructType({ r: uint8, g: uint8, b: uint8 }), Pixel = new StructType({ point: Point2D, color: Color }); • const Triangle = new ArrayType(Pixel, 3); mozilla 5 Sunday, September 18, 2011
Yet more approved for ES6 • Binary data: • const Point2D = new StructType({ x: uint32, y: uint32 }), Color = new StructType({ r: uint8, g: uint8, b: uint8 }), Pixel = new StructType({ point: Point2D, color: Color }); • const Triangle = new ArrayType(Pixel, 3); • new Triangle([{ point: { x: 0, y: 0 }, color: { r: 255, g: 255, b: 255 } }, { point: { x: 5, y: 5 }, color: { r: 128, g: 0, b: 0 } }, { point: { x: 10, y: 0 }, color: { r: 0, g: 0, b: 128 } }]); mozilla 5 Sunday, September 18, 2011
Quasi-Literals mozilla 6 Sunday, September 18, 2011
Quasi-Literals • Injection-safer string interpolation and domain-specific languages mozilla 6 Sunday, September 18, 2011
Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: mozilla 6 Sunday, September 18, 2011
Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: • quasi`literalPart1${substitution}literalPart2` desugars to mozilla 6 Sunday, September 18, 2011
Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: • quasi`literalPart1${substitution}literalPart2` desugars to • quasi({raw: ["literalPart1", "literalPart1"], unescaped: ["literalPart1", "literalPart1"]}, substitution) mozilla 6 Sunday, September 18, 2011
Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: • quasi`literalPart1${substitution}literalPart2` desugars to • quasi({raw: ["literalPart1", "literalPart1"], unescaped: ["literalPart1", "literalPart1"]}, substitution) • Multiline string literals w/o prefix: `literalPart1${substitution} (yes, that was a newline!) literalPart2` mozilla 6 Sunday, September 18, 2011
Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: • quasi`literalPart1${substitution}literalPart2` desugars to • quasi({raw: ["literalPart1", "literalPart1"], unescaped: ["literalPart1", "literalPart1"]}, substitution) • Multiline string literals w/o prefix: `literalPart1${substitution} (yes, that was a newline!) literalPart2` mozilla • Multiline regexp literals: re`literalPart1${substitution} (yes, that was a newline!) w+ literalPart2` 6 Sunday, September 18, 2011
Classes made it, barely (Yay, I think? Why am I sad?) mozilla 7 Sunday, September 18, 2011
Classes made it, barely (Yay, I think? Why am I sad?) • Sugar for prototypal object pattern, also supports closure patterns: mozilla 7 Sunday, September 18, 2011
Classes made it, barely (Yay, I think? Why am I sad?) • Sugar for prototypal object pattern, also supports closure patterns: • class Point { constructor(x, y) { private x = x, y = y; public closed_r() { return Math.sqrt(x*x + y*y); } } get x() { return @x; } get y() { return @y; } equals(p) { return @x === p@x && @y === p@y; } proto_r() { return Math.sqrt(@x * @x + @y * @y); } } mozilla 7 Sunday, September 18, 2011
Classes made it, barely (Yay, I think? Why am I sad?) • Sugar for prototypal object pattern, also supports closure patterns: • class Point { constructor(x, y) { private x = x, y = y; public closed_r() { return Math.sqrt(x*x + y*y); } } get x() { return @x; } get y() { return @y; } equals(p) { return @x === p@x && @y === p@y; } proto_r() { return Math.sqrt(@x * @x + @y * @y); } } • Private member reference syntax (@x, p@x) still up in the air... mozilla 7 Sunday, September 18, 2011
Classes made it, barely (Yay, I think? Why am I sad?) • Sugar for prototypal object pattern, also supports closure patterns: • class Point { constructor(x, y) { private x = x, y = y; public closed_r() { return Math.sqrt(x*x + y*y); } } get x() { return @x; } get y() { return @y; } equals(p) { return @x === p@x && @y === p@y; } proto_r() { return Math.sqrt(@x * @x + @y * @y); } } • Private member reference syntax (@x, p@x) still up in the air... • extends, prototype, and super work the way you want mozilla 7 Sunday, September 18, 2011
Not yet in Harmony: arrow function syntax mozilla 8 Sunday, September 18, 2011
Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) mozilla 8 Sunday, September 18, 2011
Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x mozilla 8 Sunday, September 18, 2011
Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x • Expression body: const square = (x) -> (x * x) mozilla 8 Sunday, September 18, 2011
Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x • Expression body: const square = (x) -> (x * x) • Statement body: let countUsed = (str) -> { if (str in usedWords) usedWords[str]++; else usedWords[str] = 1; } mozilla 8 Sunday, September 18, 2011
Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x • Expression body: const square = (x) -> (x * x) • Statement body: let countUsed = (str) -> { if (str in usedWords) usedWords[str]++; else usedWords[str] = 1; } • Fat arrow too: callback = (msg) => ( this.vmail.push(msg) ) mozilla 8 Sunday, September 18, 2011
Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x • Expression body: const square = (x) -> (x * x) • Statement body: let countUsed = (str) -> { if (str in usedWords) usedWords[str]++; else usedWords[str] = 1; } • Fat arrow too: callback = (msg) => ( this.vmail.push(msg) ) • Binding forms: let f() -> “writable” const K() -> “readonly” mozilla 8 Sunday, September 18, 2011
Not yet in Harmony: block lambda revival • Inspired by Smalltalk via Ruby let empty = {||}; // no need for space between bars assert(empty() === undefined); assert(typeof empty === "function"); // native and implements [[Call]] assert(empty.length === 0);   let identity = {|x| x}; // completion is return value   assert(identity(42) === 42); assert(identity.length === 1);   let a = [1, 2, 3, 4]; let b = a.map {|e| e * e} // paren-free call with block is // idiomatic control structure so // no semicolon at end mozilla print(b); // [1, 4, 9, 16] 9 Sunday, September 18, 2011
More block lambda revival • Paren-free calls, control effects: you know you want it... b = a.map {|e| // newline in block ok e * e * e} // newline after ends call   function find_first_odd(a) { a.forEach { |e, i| if (e & 1) return i; } // returns from function return -1; }   function escape_return() { return {|e| return e}; } b = escape_return(); try { b(42); } catch (e) {} // error, return from // inactive function mozilla 10 Sunday, September 18, 2011
Syntax, yay mozilla 11 Sunday, September 18, 2011
Syntax, yay • Do we need shorter function syntax at all? mozilla 11 Sunday, September 18, 2011
Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” mozilla 11 Sunday, September 18, 2011
Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” • Others say yes, but divide into roughly three camps: mozilla 11 Sunday, September 18, 2011
Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” • Others say yes, but divide into roughly three camps: • Arrow function syntax, as in CoffeeScript. mozilla 11 Sunday, September 18, 2011
Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” • Others say yes, but divide into roughly three camps: • Arrow function syntax, as in CoffeeScript. • Block lambdas. @jashkenas: “For the record, I too favor [block lambdas] if arrows in JS will need curlies to delimit blocks. Curlies or arrows, not both.” mozilla 11 Sunday, September 18, 2011
Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” • Others say yes, but divide into roughly three camps: • Arrow function syntax, as in CoffeeScript. • Block lambdas. @jashkenas: “For the record, I too favor [block lambdas] if arrows in JS will need curlies to delimit blocks. Curlies or arrows, not both.” • Some leading ugly character, maybe -- unsure about this, return. mozilla 11 Sunday, September 18, 2011
Dart to the heart Sunday, September 18, 2011
Dart to the heart • Some things I’ve heard & read Sunday, September 18, 2011
Dart to the heart • Some things I’ve heard & read • “If JavaScript does not have {classes, “guards”}, then it will be REPLACED!” [May 2010 TC39 meeting] Sunday, September 18, 2011
Dart to the heart • Some things I’ve heard & read • “If JavaScript does not have {classes, “guards”}, then it will be REPLACED!” [May 2010 TC39 meeting] • “better performance profile” Sunday, September 18, 2011
Dart to the heart • Some things I’ve heard & read • “If JavaScript does not have {classes, “guards”}, then it will be REPLACED!” [May 2010 TC39 meeting] • “better performance profile” • “amenable to tooling”, “(e.g. with optional types)” Sunday, September 18, 2011
Dart to the heart • Some things I’ve heard & read • “If JavaScript does not have {classes, “guards”}, then it will be REPLACED!” [May 2010 TC39 meeting] • “better performance profile” • “amenable to tooling”, “(e.g. with optional types)” • “Fundamental problems [like the] single Number primitive....” Sunday, September 18, 2011
iOS, lolwut? mozilla 13 Sunday, September 18, 2011
iOS, lolwut? • Leaked memo: “The emergence of compelling alternative platforms like iOS has meant that the web platform must compete on its merits, not just its reach.” mozilla 13 Sunday, September 18, 2011
iOS, lolwut? • Leaked memo: “The emergence of compelling alternative platforms like iOS has meant that the web platform must compete on its merits, not just its reach.” • m-k-s on Hacker News: “If they think per the leaked mail that devs are choosing iOS over browsers because of JS, they have their heads in the sand. Those choices are happening due to iOS as a platform not because devs are somehow so much more happier learning/using Objective-C! The best thing that Google could do is to KEEP working hard on improving the browser platform.” mozilla 13 Sunday, September 18, 2011
Food for thought mozilla 14 Sunday, September 18, 2011
Food for thought • The “REPLACED” threat and “optional types” suggest either mozilla 14 Sunday, September 18, 2011
Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] mozilla 14 Sunday, September 18, 2011
Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 mozilla 14 Sunday, September 18, 2011
Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 • Syntax: let i :: int = 0; function f(a :: G)... mozilla 14 Sunday, September 18, 2011
Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 • Syntax: let i :: int = 0; function f(a :: G)... • Semantics are runtime-pluggable, tie into trademarks proposal (nominal) mozilla 14 Sunday, September 18, 2011
Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 • Syntax: let i :: int = 0; function f(a :: G)... • Semantics are runtime-pluggable, tie into trademarks proposal (nominal) • Proposals came at last minute (May TC39 meeting), not ready for ES6 mozilla 14 Sunday, September 18, 2011
Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 • Syntax: let i :: int = 0; function f(a :: G)... • Semantics are runtime-pluggable, tie into trademarks proposal (nominal) • Proposals came at last minute (May TC39 meeting), not ready for ES6 • Why not int32, int64, bignum, as well as number (double)? mozilla 14 Sunday, September 18, 2011
The trouble with numbers mozilla 15 Sunday, September 18, 2011
The trouble with numbers • How to introduce a sane numeric tower for JS? mozilla 15 Sunday, September 18, 2011
The trouble with numbers • How to introduce a sane numeric tower for JS? • Suffixes: 4294967295u + 1 === 0u, 2147483647i + 1 === -2147483648i; // WTF! mozilla 15 Sunday, September 18, 2011
The trouble with numbers • How to introduce a sane numeric tower for JS? • Suffixes: 4294967295u + 1 === 0u, 2147483647i + 1 === -2147483648i; // WTF! • Promotion rules as in C, but with dynamic types mozilla 15 Sunday, September 18, 2011
The trouble with numbers • How to introduce a sane numeric tower for JS? • Suffixes: 4294967295u + 1 === 0u, 2147483647i + 1 === -2147483648i; // WTF! • Promotion rules as in C, but with dynamic types • This smells like trouble mozilla 15 Sunday, September 18, 2011
The trouble with numbers • How to introduce a sane numeric tower for JS? • Suffixes: 4294967295u + 1 === 0u, 2147483647i + 1 === -2147483648i; // WTF! • Promotion rules as in C, but with dynamic types • This smells like trouble • Better: use bignum arithmetic; use int arithmetic; etc. mozilla 15 Sunday, September 18, 2011
Better performance predictability mozilla 16 Sunday, September 18, 2011
Better performance predictability • JS engines currently have performance predictability problems, it’s true mozilla 16 Sunday, September 18, 2011
Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths mozilla 16 Sunday, September 18, 2011
Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths • Array holes, prototype properties being deleted, unshadowing/fore-shadowing all hurt a bit mozilla 16 Sunday, September 18, 2011
Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths • Array holes, prototype properties being deleted, unshadowing/fore-shadowing all hurt a bit • But JS engines are still improving rapidly (e.g. the SpiderMonkey Type Inference work by Brian Hackett) mozilla 16 Sunday, September 18, 2011
Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths • Array holes, prototype properties being deleted, unshadowing/fore-shadowing all hurt a bit • But JS engines are still improving rapidly (e.g. the SpiderMonkey Type Inference work by Brian Hackett) • It’s way too soon to throw in the towel mozilla 16 Sunday, September 18, 2011
Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths • Array holes, prototype properties being deleted, unshadowing/fore-shadowing all hurt a bit • But JS engines are still improving rapidly (e.g. the SpiderMonkey Type Inference work by Brian Hackett) • It’s way too soon to throw in the towel • We could add more opt-into-high-performance knobs, but: No. mozilla 16 Sunday, September 18, 2011
Harmony tune-up mozilla 17 Sunday, September 18, 2011
Harmony tune-up • It’s good to question the process mozilla 17 Sunday, September 18, 2011
Harmony tune-up • It’s good to question the process • Harmony is both conservative (consensus is hard to achieve) and path- dependent (because macro research takes time, we’re adding syntactic special forms that could be macros -- if only we had macros) mozilla 17 Sunday, September 18, 2011
Harmony tune-up • It’s good to question the process • Harmony is both conservative (consensus is hard to achieve) and path- dependent (because macro research takes time, we’re adding syntactic special forms that could be macros -- if only we had macros) • Should we take the Dart clues to heart, without over-reacting? mozilla 17 Sunday, September 18, 2011
Harmony tune-up • It’s good to question the process • Harmony is both conservative (consensus is hard to achieve) and path- dependent (because macro research takes time, we’re adding syntactic special forms that could be macros -- if only we had macros) • Should we take the Dart clues to heart, without over-reacting? • My suggestion is to prototype in SpiderMonkey and V8 some of the strawman proposals that did not make ES6 now, and see if any deserve promotion to ES6 mozilla 17 Sunday, September 18, 2011
RiverTrail: Parallel JS mozilla 18 Sunday, September 18, 2011
RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. mozilla 18 Sunday, September 18, 2011
RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results mozilla 18 Sunday, September 18, 2011
RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results • Relies on commutativity to parallelize arithmetic operations (this does inject some f.p. non-determinism). mozilla 18 Sunday, September 18, 2011
RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results • Relies on commutativity to parallelize arithmetic operations (this does inject some f.p. non-determinism). • A Firefox add-on that runs a Narcissus-based JS-to-OpenCL compiler over ParallelArray code mozilla 18 Sunday, September 18, 2011
RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results • Relies on commutativity to parallelize arithmetic operations (this does inject some f.p. non-determinism). • A Firefox add-on that runs a Narcissus-based JS-to-OpenCL compiler over ParallelArray code • Source: github.com/RiverTrail/RiverTrail (user id should’ve been IntelLabs) mozilla 18 Sunday, September 18, 2011
RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results • Relies on commutativity to parallelize arithmetic operations (this does inject some f.p. non-determinism). • A Firefox add-on that runs a Narcissus-based JS-to-OpenCL compiler over ParallelArray code • Source: github.com/RiverTrail/RiverTrail (user id should’ve been IntelLabs) • Demo code is funny: it contains a "DO NOT use strict”; directive! mozilla 18 Sunday, September 18, 2011
RiverTrail demo sample code • the ParallelArray constructor builds on typed arrays: NBody.private.initVel = new Array(numBodies); NBody.private.initVelTA = new Float32Array(numBodies * 4); var initAsteroidPos = new Array(50); for (i = 0; i < 50; i++) {     initAsteroidPos[i] = new ParallelArray([                                             NBody.private.posTA[i * 3 + 0],     // x                                             NBody.private.posTA[i * 3 + 1],                                             NBody.private.posTA[i * 3 + 2],                                             ]); }   . . . NBody.private.asteroidPos = new ParallelArray(Float32Array, initAsteroidPos);   . . . NBody.private.vel = new ParallelArray(Float32Array, NBody.private.initVel); mozilla 19 Sunday, September 18, 2011
ParallelArray methods in action • combine method is a workhorse (takes variable number of args) "animateTickParallel": function animateTickParallel() {     // increment (+=) velocity by acceleration     var newVel = NBody.private.vel.combine(                  1,                      low_precision(NBody.bodyVelocityLoopified),                      NBody.private.pos,                      numBodies,                      NBody.Constant.deltaTime,                      NBody.Constant.epsSqr,                      NBody.time,                      NBody.private.asteroidPos                  );   . . . mozilla 20 Sunday, September 18, 2011
Always bet on JS Sunday, September 18, 2011
Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” Sunday, September 18, 2011
Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast Sunday, September 18, 2011
Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast • Then they said it couldn’t be fixed Sunday, September 18, 2011
Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast • Then they said it couldn’t be fixed • Then it couldn’t do multicore/GPU Sunday, September 18, 2011
Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast • Then they said it couldn’t be fixed • Then it couldn’t do multicore/GPU • Wrong every time! Sunday, September 18, 2011
Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast • Then they said it couldn’t be fixed • Then it couldn’t do multicore/GPU • Wrong every time! • My advice: always bet on JS Sunday, September 18, 2011
Q&A • @BrendanEich on twitter • brendan@mozilla.org • es-discuss@mozilla.org mozilla 22 Sunday, September 18, 2011

Recommended

JSLOL
JSLOLJSLOL
JSLOLBrendan Eich
 
Txjs talk
Txjs talkTxjs talk
Txjs talkBrendan Eich
 
ES.next
ES.nextES.next
ES.nextBrendan Eich
 
MSR Talk
MSR TalkMSR Talk
MSR TalkBrendan Eich
 
Building Languages for the JVM - StarTechConf 2011
Building Languages for the JVM - StarTechConf 2011Building Languages for the JVM - StarTechConf 2011
Building Languages for the JVM - StarTechConf 2011Charles Nutter
 
Splash
SplashSplash
SplashBrendan Eich
 
Javaland keynote final
Javaland keynote finalJavaland keynote final
Javaland keynote finalMarcus Lagergren
 
Introduction to Linked Data: RDF Vocabularies
Introduction to Linked Data: RDF VocabulariesIntroduction to Linked Data: RDF Vocabularies
Introduction to Linked Data: RDF VocabulariesDavid Wood
 

Recommended

JSLOL
JSLOLJSLOL
JSLOLBrendan Eich
 
Txjs talk
Txjs talkTxjs talk
Txjs talkBrendan Eich
 
ES.next
ES.nextES.next
ES.nextBrendan Eich
 
MSR Talk
MSR TalkMSR Talk
MSR TalkBrendan Eich
 
Building Languages for the JVM - StarTechConf 2011
Building Languages for the JVM - StarTechConf 2011Building Languages for the JVM - StarTechConf 2011
Building Languages for the JVM - StarTechConf 2011Charles Nutter
 
Splash
SplashSplash
SplashBrendan Eich
 
Javaland keynote final
Javaland keynote finalJavaland keynote final
Javaland keynote finalMarcus Lagergren
 
Introduction to Linked Data: RDF Vocabularies
Introduction to Linked Data: RDF VocabulariesIntroduction to Linked Data: RDF Vocabularies
Introduction to Linked Data: RDF VocabulariesDavid Wood
 
Paren free
Paren freeParen free
Paren freeBrendan Eich
 
Web futures
Web futuresWeb futures
Web futuresBrendan Eich
 
Mozilla's NodeConf talk
Mozilla's NodeConf talkMozilla's NodeConf talk
Mozilla's NodeConf talkBrendan Eich
 
Fluent14
Fluent14Fluent14
Fluent14Brendan Eich
 
Taysom seminar
Taysom seminarTaysom seminar
Taysom seminarBrendan Eich
 
Fluent15
Fluent15Fluent15
Fluent15Brendan Eich
 
My dotJS Talk
My dotJS TalkMy dotJS Talk
My dotJS TalkBrendan Eich
 
JS Responsibilities
JS ResponsibilitiesJS Responsibilities
JS ResponsibilitiesBrendan Eich
 
Mozilla Research Party Talk
Mozilla Research Party TalkMozilla Research Party Talk
Mozilla Research Party TalkBrendan Eich
 
dotJS 2015
dotJS 2015dotJS 2015
dotJS 2015Brendan Eich
 
Always bet on JS - Finjs.io NYC 2016
Always bet on JS - Finjs.io NYC 2016Always bet on JS - Finjs.io NYC 2016
Always bet on JS - Finjs.io NYC 2016Brendan Eich
 
Extensible Operators and Literals for JavaScript
Extensible Operators and Literals for JavaScriptExtensible Operators and Literals for JavaScript
Extensible Operators and Literals for JavaScriptBrendan Eich
 
Value Objects, Full Throttle (to be updated for spring TC39 meetings)
Value Objects, Full Throttle (to be updated for spring TC39 meetings)Value Objects, Full Throttle (to be updated for spring TC39 meetings)
Value Objects, Full Throttle (to be updated for spring TC39 meetings)Brendan Eich
 
Value objects in JS - an ES7 work in progress
Value objects in JS - an ES7 work in progressValue objects in JS - an ES7 work in progress
Value objects in JS - an ES7 work in progressBrendan Eich
 
The Same-Origin Saga
The Same-Origin SagaThe Same-Origin Saga
The Same-Origin SagaBrendan Eich
 
Int64
Int64Int64
Int64Brendan Eich
 
A Re-Introduction to Third-Party Scripting
A Re-Introduction to Third-Party ScriptingA Re-Introduction to Third-Party Scripting
A Re-Introduction to Third-Party Scriptingbenvinegar
 
Re-Introduction to Third-party Scripting
Re-Introduction to Third-party ScriptingRe-Introduction to Third-party Scripting
Re-Introduction to Third-party Scriptingbenvinegar
 
Nodes Cck And Panels
Nodes Cck And PanelsNodes Cck And Panels
Nodes Cck And Panelsjskulski
 
Future Tense
Future TenseFuture Tense
Future TenseBrendan Eich
 
Go - The Power Of Simplicity
Go - The Power Of SimplicityGo - The Power Of Simplicity
Go - The Power Of SimplicityEduardo Nunes Pereira
 
Evolution of Programming Languages.pdf
Evolution of Programming Languages.pdfEvolution of Programming Languages.pdf
Evolution of Programming Languages.pdfMadurai Kamaraj University Madurai Tamil Nadu India
 

More Related Content

Viewers also liked

Mozilla's NodeConf talk
Mozilla's NodeConf talkMozilla's NodeConf talk
Mozilla's NodeConf talkBrendan Eich
 
JS Responsibilities
JS ResponsibilitiesJS Responsibilities
JS ResponsibilitiesBrendan Eich
 
Mozilla Research Party Talk
Mozilla Research Party TalkMozilla Research Party Talk
Mozilla Research Party TalkBrendan Eich
 
Always bet on JS - Finjs.io NYC 2016
Always bet on JS - Finjs.io NYC 2016Always bet on JS - Finjs.io NYC 2016
Always bet on JS - Finjs.io NYC 2016Brendan Eich
 
Extensible Operators and Literals for JavaScript
Extensible Operators and Literals for JavaScriptExtensible Operators and Literals for JavaScript
Extensible Operators and Literals for JavaScriptBrendan Eich
 
Value Objects, Full Throttle (to be updated for spring TC39 meetings)
Value Objects, Full Throttle (to be updated for spring TC39 meetings)Value Objects, Full Throttle (to be updated for spring TC39 meetings)
Value Objects, Full Throttle (to be updated for spring TC39 meetings)Brendan Eich
 
Value objects in JS - an ES7 work in progress
Value objects in JS - an ES7 work in progressValue objects in JS - an ES7 work in progress
Value objects in JS - an ES7 work in progressBrendan Eich
 
The Same-Origin Saga
The Same-Origin SagaThe Same-Origin Saga
The Same-Origin SagaBrendan Eich
 

Viewers also liked (16)

Paren free
Paren freeParen free
Paren free
 
Web futures
Web futuresWeb futures
Web futures
 
Mozilla's NodeConf talk
Mozilla's NodeConf talkMozilla's NodeConf talk
Mozilla's NodeConf talk
 
Fluent14
Fluent14Fluent14
Fluent14
 
Taysom seminar
Taysom seminarTaysom seminar
Taysom seminar
 
Fluent15
Fluent15Fluent15
Fluent15
 
My dotJS Talk
My dotJS TalkMy dotJS Talk
My dotJS Talk
 
JS Responsibilities
JS ResponsibilitiesJS Responsibilities
JS Responsibilities
 
Mozilla Research Party Talk
Mozilla Research Party TalkMozilla Research Party Talk
Mozilla Research Party Talk
 
dotJS 2015
dotJS 2015dotJS 2015
dotJS 2015
 
Always bet on JS - Finjs.io NYC 2016
Always bet on JS - Finjs.io NYC 2016Always bet on JS - Finjs.io NYC 2016
Always bet on JS - Finjs.io NYC 2016
 
Extensible Operators and Literals for JavaScript
Extensible Operators and Literals for JavaScriptExtensible Operators and Literals for JavaScript
Extensible Operators and Literals for JavaScript
 
Value Objects, Full Throttle (to be updated for spring TC39 meetings)
Value Objects, Full Throttle (to be updated for spring TC39 meetings)Value Objects, Full Throttle (to be updated for spring TC39 meetings)
Value Objects, Full Throttle (to be updated for spring TC39 meetings)
 
Value objects in JS - an ES7 work in progress
Value objects in JS - an ES7 work in progressValue objects in JS - an ES7 work in progress
Value objects in JS - an ES7 work in progress
 
The Same-Origin Saga
The Same-Origin SagaThe Same-Origin Saga
The Same-Origin Saga
 
Int64
Int64Int64
Int64
 

Similar to Capitol js

A Re-Introduction to Third-Party Scripting
A Re-Introduction to Third-Party ScriptingA Re-Introduction to Third-Party Scripting
A Re-Introduction to Third-Party Scriptingbenvinegar
 
Re-Introduction to Third-party Scripting
Re-Introduction to Third-party ScriptingRe-Introduction to Third-party Scripting
Re-Introduction to Third-party Scriptingbenvinegar
 
Nodes Cck And Panels
Nodes Cck And PanelsNodes Cck And Panels
Nodes Cck And Panelsjskulski
 
Porting E-poetry: The Case of First Screening
Porting E-poetry: The Case of First ScreeningPorting E-poetry: The Case of First Screening
Porting E-poetry: The Case of First ScreeningLeonardo Flores
 
Introduction to Cross Platform Development with Xamarin/ Visual Studio
Introduction to Cross Platform Development with Xamarin/ Visual StudioIntroduction to Cross Platform Development with Xamarin/ Visual Studio
Introduction to Cross Platform Development with Xamarin/ Visual StudioIndyMobileNetDev
 
Introduction to Go
Introduction to GoIntroduction to Go
Introduction to Gozhubert
 
NoTube User Model slides
NoTube User Model slidesNoTube User Model slides
NoTube User Model slidesDan Brickley
 
"The Past Present and Future of the Mozilla Foundation" by Zak Greant @ eLibe...
"The Past Present and Future of the Mozilla Foundation" by Zak Greant @ eLibe..."The Past Present and Future of the Mozilla Foundation" by Zak Greant @ eLibe...
"The Past Present and Future of the Mozilla Foundation" by Zak Greant @ eLibe...eLiberatica
 
Forking Successfully - or is a branch better?
Forking Successfully - or is a branch better?Forking Successfully - or is a branch better?
Forking Successfully - or is a branch better?Colin Charles
 
Web application development - The past, the present, the future
Web application development - The past, the present, the futureWeb application development - The past, the present, the future
Web application development - The past, the present, the futureJuho Vepsäläinen
 
2016 bioinformatics i_python_part_1_wim_vancriekinge
2016 bioinformatics i_python_part_1_wim_vancriekinge2016 bioinformatics i_python_part_1_wim_vancriekinge
2016 bioinformatics i_python_part_1_wim_vancriekingeProf. Wim Van Criekinge
 
Webinar Mobile ECM Apps with Nuxeo EP
Webinar Mobile ECM Apps with Nuxeo EPWebinar Mobile ECM Apps with Nuxeo EP
Webinar Mobile ECM Apps with Nuxeo EPNuxeo
 
I phone udvikling best brains
I phone udvikling best brainsI phone udvikling best brains
I phone udvikling best brainsOve larsen
 
5 Realms for Learning iOS Development
5 Realms for Learning iOS Development5 Realms for Learning iOS Development
5 Realms for Learning iOS Developmentirving-ios-jumpstart
 

Similar to Capitol js (20)

A Re-Introduction to Third-Party Scripting
A Re-Introduction to Third-Party ScriptingA Re-Introduction to Third-Party Scripting
A Re-Introduction to Third-Party Scripting
 
Re-Introduction to Third-party Scripting
Re-Introduction to Third-party ScriptingRe-Introduction to Third-party Scripting
Re-Introduction to Third-party Scripting
 
Nodes Cck And Panels
Nodes Cck And PanelsNodes Cck And Panels
Nodes Cck And Panels
 
Future Tense
Future TenseFuture Tense
Future Tense
 
Go - The Power Of Simplicity
Go - The Power Of SimplicityGo - The Power Of Simplicity
Go - The Power Of Simplicity
 
Evolution of Programming Languages.pdf
Evolution of Programming Languages.pdfEvolution of Programming Languages.pdf
Evolution of Programming Languages.pdf
 
Evolution of Programming Languages.pdf
Evolution of Programming Languages.pdfEvolution of Programming Languages.pdf
Evolution of Programming Languages.pdf
 
Porting E-poetry: The Case of First Screening
Porting E-poetry: The Case of First ScreeningPorting E-poetry: The Case of First Screening
Porting E-poetry: The Case of First Screening
 
Rust 101 (2017 edition)
Rust 101 (2017 edition)Rust 101 (2017 edition)
Rust 101 (2017 edition)
 
Introduction to Cross Platform Development with Xamarin/ Visual Studio
Introduction to Cross Platform Development with Xamarin/ Visual StudioIntroduction to Cross Platform Development with Xamarin/ Visual Studio
Introduction to Cross Platform Development with Xamarin/ Visual Studio
 
Introduction to Go
Introduction to GoIntroduction to Go
Introduction to Go
 
NoTube User Model slides
NoTube User Model slidesNoTube User Model slides
NoTube User Model slides
 
"The Past Present and Future of the Mozilla Foundation" by Zak Greant @ eLibe...
"The Past Present and Future of the Mozilla Foundation" by Zak Greant @ eLibe..."The Past Present and Future of the Mozilla Foundation" by Zak Greant @ eLibe...
"The Past Present and Future of the Mozilla Foundation" by Zak Greant @ eLibe...
 
Forking Successfully - or is a branch better?
Forking Successfully - or is a branch better?Forking Successfully - or is a branch better?
Forking Successfully - or is a branch better?
 
Web application development - The past, the present, the future
Web application development - The past, the present, the futureWeb application development - The past, the present, the future
Web application development - The past, the present, the future
 
2016 bioinformatics i_python_part_1_wim_vancriekinge
2016 bioinformatics i_python_part_1_wim_vancriekinge2016 bioinformatics i_python_part_1_wim_vancriekinge
2016 bioinformatics i_python_part_1_wim_vancriekinge
 
Monorepo at Pinterest
Monorepo at PinterestMonorepo at Pinterest
Monorepo at Pinterest
 
Webinar Mobile ECM Apps with Nuxeo EP
Webinar Mobile ECM Apps with Nuxeo EPWebinar Mobile ECM Apps with Nuxeo EP
Webinar Mobile ECM Apps with Nuxeo EP
 
I phone udvikling best brains
I phone udvikling best brainsI phone udvikling best brains
I phone udvikling best brains
 
5 Realms for Learning iOS Development
5 Realms for Learning iOS Development5 Realms for Learning iOS Development
5 Realms for Learning iOS Development
 

Recently uploaded

2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...Martijn de Jong
 
04-2024-HHUG-Sales-and-Marketing-Alignment.pptx
04-2024-HHUG-Sales-and-Marketing-Alignment.pptx04-2024-HHUG-Sales-and-Marketing-Alignment.pptx
04-2024-HHUG-Sales-and-Marketing-Alignment.pptxHampshireHUG
 
Presentation on how to chat with PDF using ChatGPT code interpreter
Presentation on how to chat with PDF using ChatGPT code interpreterPresentation on how to chat with PDF using ChatGPT code interpreter
Presentation on how to chat with PDF using ChatGPT code interpreternaman860154
 
08448380779 Call Girls In Civil Lines Women Seeking Men
08448380779 Call Girls In Civil Lines Women Seeking Men08448380779 Call Girls In Civil Lines Women Seeking Men
08448380779 Call Girls In Civil Lines Women Seeking MenDelhi Call girls
 
The Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdf
The Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdfThe Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdf
The Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdfEnterprise Knowledge
 
Scaling API-first – The story of a global engineering organization
Scaling API-first – The story of a global engineering organizationScaling API-first – The story of a global engineering organization
Scaling API-first – The story of a global engineering organizationRadu Cotescu
 
Top 5 Benefits OF Using Muvi Live Paywall For Live Streams
Top 5 Benefits OF Using Muvi Live Paywall For Live StreamsTop 5 Benefits OF Using Muvi Live Paywall For Live Streams
Top 5 Benefits OF Using Muvi Live Paywall For Live StreamsRoshan Dwivedi
 
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...Neo4j
 
Exploring the Future Potential of AI-Enabled Smartphone Processors
Exploring the Future Potential of AI-Enabled Smartphone ProcessorsExploring the Future Potential of AI-Enabled Smartphone Processors
Exploring the Future Potential of AI-Enabled Smartphone Processorsdebabhi2
 
A Call to Action for Generative AI in 2024
A Call to Action for Generative AI in 2024A Call to Action for Generative AI in 2024
A Call to Action for Generative AI in 2024Results
 
Finology Group – Insurtech Innovation Award 2024
Finology Group – Insurtech Innovation Award 2024Finology Group – Insurtech Innovation Award 2024
Finology Group – Insurtech Innovation Award 2024The Digital Insurer
 
How to Troubleshoot Apps for the Modern Connected Worker
How to Troubleshoot Apps for the Modern Connected WorkerHow to Troubleshoot Apps for the Modern Connected Worker
How to Troubleshoot Apps for the Modern Connected WorkerThousandEyes
 
IAC 2024 - IA Fast Track to Search Focused AI Solutions
IAC 2024 - IA Fast Track to Search Focused AI SolutionsIAC 2024 - IA Fast Track to Search Focused AI Solutions
IAC 2024 - IA Fast Track to Search Focused AI SolutionsEnterprise Knowledge
 
Kalyanpur ) Call Girls in Lucknow Finest Escorts Service 🍸 8923113531 🎰 Avail...
Kalyanpur ) Call Girls in Lucknow Finest Escorts Service 🍸 8923113531 🎰 Avail...Kalyanpur ) Call Girls in Lucknow Finest Escorts Service 🍸 8923113531 🎰 Avail...
Kalyanpur ) Call Girls in Lucknow Finest Escorts Service 🍸 8923113531 🎰 Avail...gurkirankumar98700
 
GenCyber Cyber Security Day Presentation
GenCyber Cyber Security Day PresentationGenCyber Cyber Security Day Presentation
GenCyber Cyber Security Day PresentationMichael W. Hawkins
 
CNv6 Instructor Chapter 6 Quality of Service
CNv6 Instructor Chapter 6 Quality of ServiceCNv6 Instructor Chapter 6 Quality of Service
CNv6 Instructor Chapter 6 Quality of Servicegiselly40
 
Injustice - Developers Among Us (SciFiDevCon 2024)
Injustice - Developers Among Us (SciFiDevCon 2024)Injustice - Developers Among Us (SciFiDevCon 2024)
Injustice - Developers Among Us (SciFiDevCon 2024)Allon Mureinik
 
08448380779 Call Girls In Friends Colony Women Seeking Men
08448380779 Call Girls In Friends Colony Women Seeking Men08448380779 Call Girls In Friends Colony Women Seeking Men
08448380779 Call Girls In Friends Colony Women Seeking MenDelhi Call girls
 
Strategies for Unlocking Knowledge Management in Microsoft 365 in the Copilot...
Strategies for Unlocking Knowledge Management in Microsoft 365 in the Copilot...Strategies for Unlocking Knowledge Management in Microsoft 365 in the Copilot...
Strategies for Unlocking Knowledge Management in Microsoft 365 in the Copilot...Drew Madelung
 
Handwritten Text Recognition for manuscripts and early printed texts
Handwritten Text Recognition for manuscripts and early printed textsHandwritten Text Recognition for manuscripts and early printed texts
Handwritten Text Recognition for manuscripts and early printed textsMaria Levchenko
 

Recently uploaded (20)

2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...
 
04-2024-HHUG-Sales-and-Marketing-Alignment.pptx
04-2024-HHUG-Sales-and-Marketing-Alignment.pptx04-2024-HHUG-Sales-and-Marketing-Alignment.pptx
04-2024-HHUG-Sales-and-Marketing-Alignment.pptx
 
Presentation on how to chat with PDF using ChatGPT code interpreter
Presentation on how to chat with PDF using ChatGPT code interpreterPresentation on how to chat with PDF using ChatGPT code interpreter
Presentation on how to chat with PDF using ChatGPT code interpreter
 
08448380779 Call Girls In Civil Lines Women Seeking Men
08448380779 Call Girls In Civil Lines Women Seeking Men08448380779 Call Girls In Civil Lines Women Seeking Men
08448380779 Call Girls In Civil Lines Women Seeking Men
 
The Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdf
The Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdfThe Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdf
The Role of Taxonomy and Ontology in Semantic Layers - Heather Hedden.pdf
 
Scaling API-first – The story of a global engineering organization
Scaling API-first – The story of a global engineering organizationScaling API-first – The story of a global engineering organization
Scaling API-first – The story of a global engineering organization
 
Top 5 Benefits OF Using Muvi Live Paywall For Live Streams
Top 5 Benefits OF Using Muvi Live Paywall For Live StreamsTop 5 Benefits OF Using Muvi Live Paywall For Live Streams
Top 5 Benefits OF Using Muvi Live Paywall For Live Streams
 
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
Workshop - Best of Both Worlds_ Combine KG and Vector search for enhanced R...
 
Exploring the Future Potential of AI-Enabled Smartphone Processors
Exploring the Future Potential of AI-Enabled Smartphone ProcessorsExploring the Future Potential of AI-Enabled Smartphone Processors
Exploring the Future Potential of AI-Enabled Smartphone Processors
 
A Call to Action for Generative AI in 2024
A Call to Action for Generative AI in 2024A Call to Action for Generative AI in 2024
A Call to Action for Generative AI in 2024
 
Finology Group – Insurtech Innovation Award 2024
Finology Group – Insurtech Innovation Award 2024Finology Group – Insurtech Innovation Award 2024
Finology Group – Insurtech Innovation Award 2024
 
How to Troubleshoot Apps for the Modern Connected Worker
How to Troubleshoot Apps for the Modern Connected WorkerHow to Troubleshoot Apps for the Modern Connected Worker
How to Troubleshoot Apps for the Modern Connected Worker
 
IAC 2024 - IA Fast Track to Search Focused AI Solutions
IAC 2024 - IA Fast Track to Search Focused AI SolutionsIAC 2024 - IA Fast Track to Search Focused AI Solutions
IAC 2024 - IA Fast Track to Search Focused AI Solutions
 
Kalyanpur ) Call Girls in Lucknow Finest Escorts Service 🍸 8923113531 🎰 Avail...
Kalyanpur ) Call Girls in Lucknow Finest Escorts Service 🍸 8923113531 🎰 Avail...Kalyanpur ) Call Girls in Lucknow Finest Escorts Service 🍸 8923113531 🎰 Avail...
Kalyanpur ) Call Girls in Lucknow Finest Escorts Service 🍸 8923113531 🎰 Avail...
 
GenCyber Cyber Security Day Presentation
GenCyber Cyber Security Day PresentationGenCyber Cyber Security Day Presentation
GenCyber Cyber Security Day Presentation
 
CNv6 Instructor Chapter 6 Quality of Service
CNv6 Instructor Chapter 6 Quality of ServiceCNv6 Instructor Chapter 6 Quality of Service
CNv6 Instructor Chapter 6 Quality of Service
 
Injustice - Developers Among Us (SciFiDevCon 2024)
Injustice - Developers Among Us (SciFiDevCon 2024)Injustice - Developers Among Us (SciFiDevCon 2024)
Injustice - Developers Among Us (SciFiDevCon 2024)
 
08448380779 Call Girls In Friends Colony Women Seeking Men
08448380779 Call Girls In Friends Colony Women Seeking Men08448380779 Call Girls In Friends Colony Women Seeking Men
08448380779 Call Girls In Friends Colony Women Seeking Men
 
Strategies for Unlocking Knowledge Management in Microsoft 365 in the Copilot...
Strategies for Unlocking Knowledge Management in Microsoft 365 in the Copilot...Strategies for Unlocking Knowledge Management in Microsoft 365 in the Copilot...
Strategies for Unlocking Knowledge Management in Microsoft 365 in the Copilot...
 
Handwritten Text Recognition for manuscripts and early printed texts
Handwritten Text Recognition for manuscripts and early printed textsHandwritten Text Recognition for manuscripts and early printed texts
Handwritten Text Recognition for manuscripts and early printed texts
 

Capitol js

  • 1. Capital^H^HolJS brendan@mozilla.org Sunday, September 18, 2011
  • 2. Capital^H^HolJS brendan@mozilla.org • History, goals Sunday, September 18, 2011
  • 3. Capital^H^HolJS brendan@mozilla.org • History, goals • ES6, what’s in it? Sunday, September 18, 2011
  • 4. Capital^H^HolJS brendan@mozilla.org • History, goals • ES6, what’s in it? • Dart: I can’t wait! Sunday, September 18, 2011
  • 5. Capital^H^HolJS brendan@mozilla.org • History, goals • ES6, what’s in it? • Dart: I can’t wait! • Harmony tune-up Sunday, September 18, 2011
  • 6. Capital^H^HolJS brendan@mozilla.org • History, goals • ES6, what’s in it? • Dart: I can’t wait! • Harmony tune-up • RiverTrail demo Sunday, September 18, 2011
  • 7. A very brief history mozilla 2 Sunday, September 18, 2011
  • 8. A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java mozilla 2 Sunday, September 18, 2011
  • 9. A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) mozilla 2 Sunday, September 18, 2011
  • 10. A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) mozilla 2 Sunday, September 18, 2011
  • 11. A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk mozilla 2 Sunday, September 18, 2011
  • 12. A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk • 1999: ES3: function expressions, RegExps, try/catch/finally, switch, do-while mozilla 2 Sunday, September 18, 2011
  • 13. A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk • 1999: ES3: function expressions, RegExps, try/catch/finally, switch, do-while • 2005: the Ajax revolution, followed by “The Ajax Experience” mozilla 2 Sunday, September 18, 2011
  • 14. A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk • 1999: ES3: function expressions, RegExps, try/catch/finally, switch, do-while • 2005: the Ajax revolution, followed by “The Ajax Experience” • 2008: ES4 RIP, Harmony founded in July at the Oslo TC39 meeting mozilla 2 Sunday, September 18, 2011
  • 15. A very brief history • Ten days in May 1995: “Mocha”, form validation, img rollovers, scripting of Java • September 1995: “LiveScript” (did Netscape marketing go to Microsoft after?) • December 1995: “JavaScript”, thanks to Bill Joy (a Sun Founder) • 1996-1997: ES1 thanks to ECMA (now Ecma) TC39 -- see my TXJS talk • 1999: ES3: function expressions, RegExps, try/catch/finally, switch, do-while • 2005: the Ajax revolution, followed by “The Ajax Experience” • 2008: ES4 RIP, Harmony founded in July at the Oslo TC39 meeting mozilla • 2009: ES5: “use strict”, JSON, Object.create, etc. 2 Sunday, September 18, 2011
  • 16. The Harmony goals mozilla 3 Sunday, September 18, 2011
  • 17. The Harmony goals • Be a better language for writing: mozilla 3 Sunday, September 18, 2011
  • 18. The Harmony goals • Be a better language for writing: • complex applications mozilla 3 Sunday, September 18, 2011
  • 19. The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications mozilla 3 Sunday, September 18, 2011
  • 20. The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition mozilla 3 Sunday, September 18, 2011
  • 21. The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition • Better tests, if not a testable (executable) specification mozilla 3 Sunday, September 18, 2011
  • 22. The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition • Better tests, if not a testable (executable) specification • Adopt de facto standards where possible mozilla 3 Sunday, September 18, 2011
  • 23. The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition • Better tests, if not a testable (executable) specification • Adopt de facto standards where possible • Keep versioning as simple and linear as possible mozilla 3 Sunday, September 18, 2011
  • 24. The Harmony goals • Be a better language for writing: • complex applications • libraries (including the DOM) shared by those applications • code generators targeting the new edition • Better tests, if not a testable (executable) specification • Adopt de facto standards where possible • Keep versioning as simple and linear as possible • Support a statically verifiable, object-capability secure subset mozilla 3 Sunday, September 18, 2011
  • 25. Approved for ES6 mozilla 4 Sunday, September 18, 2011
  • 26. Approved for ES6 • let, const, function in block scope mozilla 4 Sunday, September 18, 2011
  • 27. Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() mozilla 4 Sunday, September 18, 2011
  • 28. Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} mozilla 4 Sunday, September 18, 2011
  • 29. Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) mozilla 4 Sunday, September 18, 2011
  • 30. Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) • proxies, weak maps: Proxy.create(handler, proto), new WeakMap mozilla 4 Sunday, September 18, 2011
  • 31. Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) • proxies, weak maps: Proxy.create(handler, proto), new WeakMap • modules: module M { export function fast_sin(x) {...} } mozilla 4 Sunday, September 18, 2011
  • 32. Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) • proxies, weak maps: Proxy.create(handler, proto), new WeakMap • modules: module M { export function fast_sin(x) {...} } • iterators, generators: function* gen() { yield 1; yield 2; } mozilla 4 Sunday, September 18, 2011
  • 33. Approved for ES6 • let, const, function in block scope • destructuring: let {x, y} = pt; let [s, v, o] = triple() • parameter default values: function f(x, y=1, z=0) {...} • rest, spread: function g(i, j, ...r) { return r.slice(i, j); } let a = [0,1,2,3], o = new any_constructor(...a) • proxies, weak maps: Proxy.create(handler, proto), new WeakMap • modules: module M { export function fast_sin(x) {...} } • iterators, generators: function* gen() { yield 1; yield 2; } mozilla • comprehensions: return [a+b for a of A for b of B] 4 Sunday, September 18, 2011
  • 34. Yet more approved for ES6 mozilla 5 Sunday, September 18, 2011
  • 35. Yet more approved for ES6 • Binary data: mozilla 5 Sunday, September 18, 2011
  • 36. Yet more approved for ES6 • Binary data: • const Point2D = new StructType({ x: uint32, y: uint32 }), Color = new StructType({ r: uint8, g: uint8, b: uint8 }), Pixel = new StructType({ point: Point2D, color: Color }); mozilla 5 Sunday, September 18, 2011
  • 37. Yet more approved for ES6 • Binary data: • const Point2D = new StructType({ x: uint32, y: uint32 }), Color = new StructType({ r: uint8, g: uint8, b: uint8 }), Pixel = new StructType({ point: Point2D, color: Color }); • const Triangle = new ArrayType(Pixel, 3); mozilla 5 Sunday, September 18, 2011
  • 38. Yet more approved for ES6 • Binary data: • const Point2D = new StructType({ x: uint32, y: uint32 }), Color = new StructType({ r: uint8, g: uint8, b: uint8 }), Pixel = new StructType({ point: Point2D, color: Color }); • const Triangle = new ArrayType(Pixel, 3); • new Triangle([{ point: { x: 0, y: 0 }, color: { r: 255, g: 255, b: 255 } }, { point: { x: 5, y: 5 }, color: { r: 128, g: 0, b: 0 } }, { point: { x: 10, y: 0 }, color: { r: 0, g: 0, b: 128 } }]); mozilla 5 Sunday, September 18, 2011
  • 39. Quasi-Literals mozilla 6 Sunday, September 18, 2011
  • 40. Quasi-Literals • Injection-safer string interpolation and domain-specific languages mozilla 6 Sunday, September 18, 2011
  • 41. Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: mozilla 6 Sunday, September 18, 2011
  • 42. Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: • quasi`literalPart1${substitution}literalPart2` desugars to mozilla 6 Sunday, September 18, 2011
  • 43. Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: • quasi`literalPart1${substitution}literalPart2` desugars to • quasi({raw: ["literalPart1", "literalPart1"], unescaped: ["literalPart1", "literalPart1"]}, substitution) mozilla 6 Sunday, September 18, 2011
  • 44. Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: • quasi`literalPart1${substitution}literalPart2` desugars to • quasi({raw: ["literalPart1", "literalPart1"], unescaped: ["literalPart1", "literalPart1"]}, substitution) • Multiline string literals w/o prefix: `literalPart1${substitution} (yes, that was a newline!) literalPart2` mozilla 6 Sunday, September 18, 2011
  • 45. Quasi-Literals • Injection-safer string interpolation and domain-specific languages • Backtick-quoted string desugars to a function call that operates on the literal portions and substitution results: • quasi`literalPart1${substitution}literalPart2` desugars to • quasi({raw: ["literalPart1", "literalPart1"], unescaped: ["literalPart1", "literalPart1"]}, substitution) • Multiline string literals w/o prefix: `literalPart1${substitution} (yes, that was a newline!) literalPart2` mozilla • Multiline regexp literals: re`literalPart1${substitution} (yes, that was a newline!) w+ literalPart2` 6 Sunday, September 18, 2011
  • 46. Classes made it, barely (Yay, I think? Why am I sad?) mozilla 7 Sunday, September 18, 2011
  • 47. Classes made it, barely (Yay, I think? Why am I sad?) • Sugar for prototypal object pattern, also supports closure patterns: mozilla 7 Sunday, September 18, 2011
  • 48. Classes made it, barely (Yay, I think? Why am I sad?) • Sugar for prototypal object pattern, also supports closure patterns: • class Point { constructor(x, y) { private x = x, y = y; public closed_r() { return Math.sqrt(x*x + y*y); } } get x() { return @x; } get y() { return @y; } equals(p) { return @x === p@x && @y === p@y; } proto_r() { return Math.sqrt(@x * @x + @y * @y); } } mozilla 7 Sunday, September 18, 2011
  • 49. Classes made it, barely (Yay, I think? Why am I sad?) • Sugar for prototypal object pattern, also supports closure patterns: • class Point { constructor(x, y) { private x = x, y = y; public closed_r() { return Math.sqrt(x*x + y*y); } } get x() { return @x; } get y() { return @y; } equals(p) { return @x === p@x && @y === p@y; } proto_r() { return Math.sqrt(@x * @x + @y * @y); } } • Private member reference syntax (@x, p@x) still up in the air... mozilla 7 Sunday, September 18, 2011
  • 50. Classes made it, barely (Yay, I think? Why am I sad?) • Sugar for prototypal object pattern, also supports closure patterns: • class Point { constructor(x, y) { private x = x, y = y; public closed_r() { return Math.sqrt(x*x + y*y); } } get x() { return @x; } get y() { return @y; } equals(p) { return @x === p@x && @y === p@y; } proto_r() { return Math.sqrt(@x * @x + @y * @y); } } • Private member reference syntax (@x, p@x) still up in the air... • extends, prototype, and super work the way you want mozilla 7 Sunday, September 18, 2011
  • 51. Not yet in Harmony: arrow function syntax mozilla 8 Sunday, September 18, 2011
  • 52. Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) mozilla 8 Sunday, September 18, 2011
  • 53. Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x mozilla 8 Sunday, September 18, 2011
  • 54. Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x • Expression body: const square = (x) -> (x * x) mozilla 8 Sunday, September 18, 2011
  • 55. Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x • Expression body: const square = (x) -> (x * x) • Statement body: let countUsed = (str) -> { if (str in usedWords) usedWords[str]++; else usedWords[str] = 1; } mozilla 8 Sunday, September 18, 2011
  • 56. Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x • Expression body: const square = (x) -> (x * x) • Statement body: let countUsed = (str) -> { if (str in usedWords) usedWords[str]++; else usedWords[str] = 1; } • Fat arrow too: callback = (msg) => ( this.vmail.push(msg) ) mozilla 8 Sunday, September 18, 2011
  • 57. Not yet in Harmony: arrow function syntax • Arrow function syntax, instead of λ, ƒ, or # (want to save # for later) • Just like CoffeeScript: let identity = (x) -> x • Expression body: const square = (x) -> (x * x) • Statement body: let countUsed = (str) -> { if (str in usedWords) usedWords[str]++; else usedWords[str] = 1; } • Fat arrow too: callback = (msg) => ( this.vmail.push(msg) ) • Binding forms: let f() -> “writable” const K() -> “readonly” mozilla 8 Sunday, September 18, 2011
  • 58. Not yet in Harmony: block lambda revival • Inspired by Smalltalk via Ruby let empty = {||}; // no need for space between bars assert(empty() === undefined); assert(typeof empty === "function"); // native and implements [[Call]] assert(empty.length === 0);   let identity = {|x| x}; // completion is return value   assert(identity(42) === 42); assert(identity.length === 1);   let a = [1, 2, 3, 4]; let b = a.map {|e| e * e} // paren-free call with block is // idiomatic control structure so // no semicolon at end mozilla print(b); // [1, 4, 9, 16] 9 Sunday, September 18, 2011
  • 59. More block lambda revival • Paren-free calls, control effects: you know you want it... b = a.map {|e| // newline in block ok e * e * e} // newline after ends call   function find_first_odd(a) { a.forEach { |e, i| if (e & 1) return i; } // returns from function return -1; }   function escape_return() { return {|e| return e}; } b = escape_return(); try { b(42); } catch (e) {} // error, return from // inactive function mozilla 10 Sunday, September 18, 2011
  • 60. Syntax, yay mozilla 11 Sunday, September 18, 2011
  • 61. Syntax, yay • Do we need shorter function syntax at all? mozilla 11 Sunday, September 18, 2011
  • 62. Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” mozilla 11 Sunday, September 18, 2011
  • 63. Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” • Others say yes, but divide into roughly three camps: mozilla 11 Sunday, September 18, 2011
  • 64. Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” • Others say yes, but divide into roughly three camps: • Arrow function syntax, as in CoffeeScript. mozilla 11 Sunday, September 18, 2011
  • 65. Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” • Others say yes, but divide into roughly three camps: • Arrow function syntax, as in CoffeeScript. • Block lambdas. @jashkenas: “For the record, I too favor [block lambdas] if arrows in JS will need curlies to delimit blocks. Curlies or arrows, not both.” mozilla 11 Sunday, September 18, 2011
  • 66. Syntax, yay • Do we need shorter function syntax at all? • Some say no. @mikeal: “I got 99 problems and JavaScript syntax ain’t one.” • Others say yes, but divide into roughly three camps: • Arrow function syntax, as in CoffeeScript. • Block lambdas. @jashkenas: “For the record, I too favor [block lambdas] if arrows in JS will need curlies to delimit blocks. Curlies or arrows, not both.” • Some leading ugly character, maybe -- unsure about this, return. mozilla 11 Sunday, September 18, 2011
  • 67. Dart to the heart Sunday, September 18, 2011
  • 68. Dart to the heart • Some things I’ve heard & read Sunday, September 18, 2011
  • 69. Dart to the heart • Some things I’ve heard & read • “If JavaScript does not have {classes, “guards”}, then it will be REPLACED!” [May 2010 TC39 meeting] Sunday, September 18, 2011
  • 70. Dart to the heart • Some things I’ve heard & read • “If JavaScript does not have {classes, “guards”}, then it will be REPLACED!” [May 2010 TC39 meeting] • “better performance profile” Sunday, September 18, 2011
  • 71. Dart to the heart • Some things I’ve heard & read • “If JavaScript does not have {classes, “guards”}, then it will be REPLACED!” [May 2010 TC39 meeting] • “better performance profile” • “amenable to tooling”, “(e.g. with optional types)” Sunday, September 18, 2011
  • 72. Dart to the heart • Some things I’ve heard & read • “If JavaScript does not have {classes, “guards”}, then it will be REPLACED!” [May 2010 TC39 meeting] • “better performance profile” • “amenable to tooling”, “(e.g. with optional types)” • “Fundamental problems [like the] single Number primitive....” Sunday, September 18, 2011
  • 73. iOS, lolwut? mozilla 13 Sunday, September 18, 2011
  • 74. iOS, lolwut? • Leaked memo: “The emergence of compelling alternative platforms like iOS has meant that the web platform must compete on its merits, not just its reach.” mozilla 13 Sunday, September 18, 2011
  • 75. iOS, lolwut? • Leaked memo: “The emergence of compelling alternative platforms like iOS has meant that the web platform must compete on its merits, not just its reach.” • m-k-s on Hacker News: “If they think per the leaked mail that devs are choosing iOS over browsers because of JS, they have their heads in the sand. Those choices are happening due to iOS as a platform not because devs are somehow so much more happier learning/using Objective-C! The best thing that Google could do is to KEEP working hard on improving the browser platform.” mozilla 13 Sunday, September 18, 2011
  • 76. Food for thought mozilla 14 Sunday, September 18, 2011
  • 77. Food for thought • The “REPLACED” threat and “optional types” suggest either mozilla 14 Sunday, September 18, 2011
  • 78. Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] mozilla 14 Sunday, September 18, 2011
  • 79. Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 mozilla 14 Sunday, September 18, 2011
  • 80. Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 • Syntax: let i :: int = 0; function f(a :: G)... mozilla 14 Sunday, September 18, 2011
  • 81. Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 • Syntax: let i :: int = 0; function f(a :: G)... • Semantics are runtime-pluggable, tie into trademarks proposal (nominal) mozilla 14 Sunday, September 18, 2011
  • 82. Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 • Syntax: let i :: int = 0; function f(a :: G)... • Semantics are runtime-pluggable, tie into trademarks proposal (nominal) • Proposals came at last minute (May TC39 meeting), not ready for ES6 mozilla 14 Sunday, September 18, 2011
  • 83. Food for thought • The “REPLACED” threat and “optional types” suggest either • Optional static types a la Strongtalk [Bracha & Griswold] • Optional runtime guards, as proposed for Harmony but not in ES6 • Syntax: let i :: int = 0; function f(a :: G)... • Semantics are runtime-pluggable, tie into trademarks proposal (nominal) • Proposals came at last minute (May TC39 meeting), not ready for ES6 • Why not int32, int64, bignum, as well as number (double)? mozilla 14 Sunday, September 18, 2011
  • 84. The trouble with numbers mozilla 15 Sunday, September 18, 2011
  • 85. The trouble with numbers • How to introduce a sane numeric tower for JS? mozilla 15 Sunday, September 18, 2011
  • 86. The trouble with numbers • How to introduce a sane numeric tower for JS? • Suffixes: 4294967295u + 1 === 0u, 2147483647i + 1 === -2147483648i; // WTF! mozilla 15 Sunday, September 18, 2011
  • 87. The trouble with numbers • How to introduce a sane numeric tower for JS? • Suffixes: 4294967295u + 1 === 0u, 2147483647i + 1 === -2147483648i; // WTF! • Promotion rules as in C, but with dynamic types mozilla 15 Sunday, September 18, 2011
  • 88. The trouble with numbers • How to introduce a sane numeric tower for JS? • Suffixes: 4294967295u + 1 === 0u, 2147483647i + 1 === -2147483648i; // WTF! • Promotion rules as in C, but with dynamic types • This smells like trouble mozilla 15 Sunday, September 18, 2011
  • 89. The trouble with numbers • How to introduce a sane numeric tower for JS? • Suffixes: 4294967295u + 1 === 0u, 2147483647i + 1 === -2147483648i; // WTF! • Promotion rules as in C, but with dynamic types • This smells like trouble • Better: use bignum arithmetic; use int arithmetic; etc. mozilla 15 Sunday, September 18, 2011
  • 90. Better performance predictability mozilla 16 Sunday, September 18, 2011
  • 91. Better performance predictability • JS engines currently have performance predictability problems, it’s true mozilla 16 Sunday, September 18, 2011
  • 92. Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths mozilla 16 Sunday, September 18, 2011
  • 93. Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths • Array holes, prototype properties being deleted, unshadowing/fore-shadowing all hurt a bit mozilla 16 Sunday, September 18, 2011
  • 94. Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths • Array holes, prototype properties being deleted, unshadowing/fore-shadowing all hurt a bit • But JS engines are still improving rapidly (e.g. the SpiderMonkey Type Inference work by Brian Hackett) mozilla 16 Sunday, September 18, 2011
  • 95. Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths • Array holes, prototype properties being deleted, unshadowing/fore-shadowing all hurt a bit • But JS engines are still improving rapidly (e.g. the SpiderMonkey Type Inference work by Brian Hackett) • It’s way too soon to throw in the towel mozilla 16 Sunday, September 18, 2011
  • 96. Better performance predictability • JS engines currently have performance predictability problems, it’s true • Speculation can go wrong, fall back on slow paths • Array holes, prototype properties being deleted, unshadowing/fore-shadowing all hurt a bit • But JS engines are still improving rapidly (e.g. the SpiderMonkey Type Inference work by Brian Hackett) • It’s way too soon to throw in the towel • We could add more opt-into-high-performance knobs, but: No. mozilla 16 Sunday, September 18, 2011
  • 97. Harmony tune-up mozilla 17 Sunday, September 18, 2011
  • 98. Harmony tune-up • It’s good to question the process mozilla 17 Sunday, September 18, 2011
  • 99. Harmony tune-up • It’s good to question the process • Harmony is both conservative (consensus is hard to achieve) and path- dependent (because macro research takes time, we’re adding syntactic special forms that could be macros -- if only we had macros) mozilla 17 Sunday, September 18, 2011
  • 100. Harmony tune-up • It’s good to question the process • Harmony is both conservative (consensus is hard to achieve) and path- dependent (because macro research takes time, we’re adding syntactic special forms that could be macros -- if only we had macros) • Should we take the Dart clues to heart, without over-reacting? mozilla 17 Sunday, September 18, 2011
  • 101. Harmony tune-up • It’s good to question the process • Harmony is both conservative (consensus is hard to achieve) and path- dependent (because macro research takes time, we’re adding syntactic special forms that could be macros -- if only we had macros) • Should we take the Dart clues to heart, without over-reacting? • My suggestion is to prototype in SpiderMonkey and V8 some of the strawman proposals that did not make ES6 now, and see if any deserve promotion to ES6 mozilla 17 Sunday, September 18, 2011
  • 102. RiverTrail: Parallel JS mozilla 18 Sunday, September 18, 2011
  • 103. RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. mozilla 18 Sunday, September 18, 2011
  • 104. RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results mozilla 18 Sunday, September 18, 2011
  • 105. RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results • Relies on commutativity to parallelize arithmetic operations (this does inject some f.p. non-determinism). mozilla 18 Sunday, September 18, 2011
  • 106. RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results • Relies on commutativity to parallelize arithmetic operations (this does inject some f.p. non-determinism). • A Firefox add-on that runs a Narcissus-based JS-to-OpenCL compiler over ParallelArray code mozilla 18 Sunday, September 18, 2011
  • 107. RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results • Relies on commutativity to parallelize arithmetic operations (this does inject some f.p. non-determinism). • A Firefox add-on that runs a Narcissus-based JS-to-OpenCL compiler over ParallelArray code • Source: github.com/RiverTrail/RiverTrail (user id should’ve been IntelLabs) mozilla 18 Sunday, September 18, 2011
  • 108. RiverTrail: Parallel JS • A ParallelArray library, like typed arrays but immutable. • map, reduce, combine, filter, partition, scan, scatter -- all produce fresh ParallelArray results • Relies on commutativity to parallelize arithmetic operations (this does inject some f.p. non-determinism). • A Firefox add-on that runs a Narcissus-based JS-to-OpenCL compiler over ParallelArray code • Source: github.com/RiverTrail/RiverTrail (user id should’ve been IntelLabs) • Demo code is funny: it contains a "DO NOT use strict”; directive! mozilla 18 Sunday, September 18, 2011
  • 109. RiverTrail demo sample code • the ParallelArray constructor builds on typed arrays: NBody.private.initVel = new Array(numBodies); NBody.private.initVelTA = new Float32Array(numBodies * 4); var initAsteroidPos = new Array(50); for (i = 0; i < 50; i++) {     initAsteroidPos[i] = new ParallelArray([                                             NBody.private.posTA[i * 3 + 0],     // x                                             NBody.private.posTA[i * 3 + 1],                                             NBody.private.posTA[i * 3 + 2],                                             ]); }   . . . NBody.private.asteroidPos = new ParallelArray(Float32Array, initAsteroidPos);   . . . NBody.private.vel = new ParallelArray(Float32Array, NBody.private.initVel); mozilla 19 Sunday, September 18, 2011
  • 110. ParallelArray methods in action • combine method is a workhorse (takes variable number of args) "animateTickParallel": function animateTickParallel() {     // increment (+=) velocity by acceleration     var newVel = NBody.private.vel.combine(                  1,                      low_precision(NBody.bodyVelocityLoopified),                      NBody.private.pos,                      numBodies,                      NBody.Constant.deltaTime,                      NBody.Constant.epsSqr,                      NBody.time,                      NBody.private.asteroidPos                  );   . . . mozilla 20 Sunday, September 18, 2011
  • 111. Always bet on JS Sunday, September 18, 2011
  • 112. Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” Sunday, September 18, 2011
  • 113. Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast Sunday, September 18, 2011
  • 114. Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast • Then they said it couldn’t be fixed Sunday, September 18, 2011
  • 115. Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast • Then they said it couldn’t be fixed • Then it couldn’t do multicore/GPU Sunday, September 18, 2011
  • 116. Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast • Then they said it couldn’t be fixed • Then it couldn’t do multicore/GPU • Wrong every time! Sunday, September 18, 2011
  • 117. Always bet on JS • First they said JS couldn’t be useful for buildling “rich Internet apps” • Then they said it couldn’t be fast • Then they said it couldn’t be fixed • Then it couldn’t do multicore/GPU • Wrong every time! • My advice: always bet on JS Sunday, September 18, 2011
  • 118. Q&A • @BrendanEich on twitter • brendan@mozilla.org • es-discuss@mozilla.org mozilla 22 Sunday, September 18, 2011