A quick talk given at our workplace lunch learning sessions on the different ways to destructure composite data structures in Clojure.

1. Destructuring
Demystified
Demystified
A Tour of clojure’s Destructuring forms by
someone hopelessly unqualified.

2. TIL Session #1
What is it?
Why use it?
Where should I use them?
When should I use them?
How?
Cool tricks

3. What?
“A method of positionally binding locals based on
an expected form for a composite data structure”
- The Joy of Clojure
OR
“Picking out the bits you need”
- Tom Crinson

4. Why?
A lot of times you don’t need the whole
structure.
Keeps code readable
Keeps functions focussed

5. Why?

6. Where?
let form
function parameters

7. When?
“Whenever you find yourself calling nth
repeatedly, or
looking up constants in a map or using first or next,
ask yourself if restructuring would be a better fit.”
- The Joy of Clojure

8. Vectors - Remainder
Slurp up remaining names

9. Vectors - :as
Keeps as a vector - untouched

10. Vectors - Associative
Destructuring
Declare local names as indices into a vector

11. Maps
‘Tis a bit repetitive...
And... keywords on the right?

12. Maps - keywords
:keys
:strs
:syms ...

13. Maps - default Values

14. Cool Tricks -1
Nested Destructuring

15. Cool Tricks - 2
Works on other data structures!

16. Fin