My presentation "How Xslate Works" at YAPC::Asia Tokyo 2010

1. How Xslate works The next generation's template engine YAPC::Asia Tokyo 2010, Day 2, 2010/10/16 10:10-10:50 Fuji, Goro (gfx) [email_address] http://github.com/gfx /

4. Perl/XS

5. Moose/Mouse (as Any::Moose)

9. Information

12. Multi-syntaxes (esp. TT-like syntax)

13. Kind error messages

15. my $var = sprintf 'Hello, %s world', $foo; # <- this

18. HTML::Template (and ::Pro, ::Compiled, ::JIT)

19. Text::MicroTemplate (and ::Extended)

20. Mojo::Template

21. Text::ClearSilver (a perl binding to clearsilver)

22. HTML::Mason, Text::MicroMason

27. -: Too free, only usaful to Perl programmers

31. Ristricted (you cannot call system() nor fork())

33. ClearSilver is a good template engine,

36. Xslate is at least the fastest, the most safe in the template engines on CPAN

38. new() accepts: syntax (template syntax) , module (function-based modules), function (additional functions), path (include path), cache (caching level), cache_dir (used for caches)

39. render() returns a rendered text; cannot output to filehandles directly, nor set calbacks (unlike TT)

40. See also Text::Xslate and Text::Xslate::Manual

41. Simplest example #!perl -w use 5.10.0; use strict; use Text::Xslate; my $tx = Text::Xslate-> new (); my %vars = ( lang => 'Xslate', ); # or $tx-> render ($file, vars); say $tx-> render_string (<<'EOT', vars); Hello, <: $lang :> world! EOT # -> Hello, Xslate world!

42. Xslate templates <ul> :# This is a template with the default syntax Kolon :# an one-line code starts from a colon &quot;:&quot; :# comments start from a hash symbol &quot;#&quot; :# an in-line code is surrounded by ”<:” and &quot;:>&quot; : for $list -> $item { <li> <: $item.name :> = <: $item.value :> </li> : } </ul> : include 'foo.tx' { bar => 'overrided' } :# See also ` perldoc Text::Xslate::Syntax::Kolon `

44. xslate -s TTerse -e '[% ARGV.0 %]' 'Hi, TTerse'

45. See also example files in Text-Xslate/example/

47. Safe (XSS tolerance and ristriction)

49. TTerse

51. Template cascading

52. Performance (1) Run Text-Xslate/benchmark/x-rich-env.pl!

55. i.e. Persistent PSGI applications will take the best performance

57. a type of computer security vulnerability typically found in web applications that enables malicious attackers to inject client-side script into web pages viewed by other users. (by Wikipedia)

60. -> Text::MicroTemplate, Text::Xslate

61. This is XSS tolerance

62. Modern template engines (not only in Perl) should have XSS tolerance, and in fact do so.

64. Escape $foo in perl code, because whether $foo is escaped or not is obscure from templates

65. The 'raw' filter is provided only for string literals

67. TTerse – TT2 compatible

68. Clevery – Smarty (in PHP) compatible

70. All the features are supported

71. Most optimized

73. Available by default

74. More ristricted than the original TT2

75. No plugins, exceptions, nor mysterious features

76. As good as Kolon to run-time performance

77. Highly compatible, but diffrent to the basics of escaping mechanism

79. Need to install Text::Clevery

80. With some overhead Clevery Clevery

82. No plugin namespaces are required

84. Only available in Kolon

85. See also Text-Xslate/example/{cascade.pl,cascade,tx,base.tx}

87. Parsing

89. Execution Process <: $foo :> <: $foo :> print $foo; <: $foo :> fetch_s &quot;foo&quot; print end print $foo Virtual Machine { foo => 'bar' } ”bar&quot;

91. So convert to that first:

92. &quot; print_raw 'Hello, '; print $lang; print_raw ' world!' &quot;

93. See &T::X::Parser::preprocess

95. Using Top Down Operator Precendence method

96. Explained in ” Beautiful Code ” (O'REILLY)

97. &quot; It is easy to use. It feels a lot like Recursive Descent, but with the need for less code and with significantly better performance. &quot;, Douglas Crockford introduced there.

98. See also http://javascript.crockford.com/tdop/

100. Templates -> Tokens (string) -> Symbols (T::X::Symbol) -> Nodes (T::X::Symbol)

101. Symbols (e.g. '+' for infix:<+>) know what they do

102. One easily can extend parsers by adding symbols

103. The parser entry point is &T::X::Parser::statements

105. nud : null denotation (for objects and prefixes)

112. print_raw_s &quot;Hello, &quot;

113. fetch_s &quot;lang&quot;

114. print

115. print_raw_s &quot; world!&quot;

118. Like JSON, but fast and small

119. See also http://msgpack.org/

121. Using the direct threaded code paradigm

123. An opcode (e.g. 'fetch_s') is a block of code with an argument (a sv, int, or address of opcode)

125. print # $out .= $a

126. Execution Process <: $foo :> <: $foo :> print $foo; <: $foo :> fetch_s &quot;foo&quot; print end print $foo Virtual Machine { foo => 'bar' } ” bar&quot;

129. Preallocation of the output buffer

134. Register machine (two registers + one stack)

140. Then

141. First: Save the size of a template

142. Later: Preallocate the buffer with the saved size

144. Context controls

145. Augoment block modifiers

146. More template syntaxes

147. Xslate in WAF

149. <: last if $a > 10 :> in Kolon

150. [% LAST IF a > 10 %] in TTerse

154. 'augment' like block modifiers are requested

156. Django (in Python)

157. Jinja (in Python)

158. Any ideas?

160. MojoX::Renderer::Xslate for Mojo

161. Dancer::Template::Xslate for Dancer

164. Web+DB Press Vol.59

165. Vote me! Mac Book Proほしいけどお金がありません！(>_<) もしよかったら投票お願いします！ http://yapcasia.org/2010/vote

167. A. テンプレートのレンダリングに特化しているので速い。特にエスケープしながらの連結が効果的

168. Q. XslateのVMの上でPerl6は動かせる？

169. A. 普通の言語ではないので無理

170. Q. 他の言語のバインディングは可能？

171. A. Perlと密結合しているので無理。書き直すしか

172. That's all Thanks for your attention!