lispy.el demo 5: ->>ification

Back to github This file in org-mode Function reference

Intro

This demo covers some very basic lispy commands such as:

  • move code up/down with w / s
  • grow/shrink current list with > / <

Task summary

Transform from: 

(map #(* % %) (filter odd? [1 2 3 4 5]))

to: 

(->> [1 2 3 4 5]
  (filter odd?)
  (map #(* % %)))

Screencast

The screencast for this demo is here: http://youtu.be/N7C3FX4mr_o

Step-by-step expansion

step 1

2( to wrap with parens, enter ->>: 

(->> (map #(* % %) (filter odd? [1 2 3 4 5])))

step 2

  • C-f to get into special
  • d to switch to the different side
  • < to shrink list
(->> (map #(* % %)) (filter odd? [1 2 3 4 5]))

step 3

  • j to move the cursor down by one sexp
  • < to shrink again
(->> (map #(* % %)) (filter odd?) [1 2 3 4 5])

step 4

  • j to move the cursor down
  • ww to move the expression up twice
(->> [1 2 3 4 5] (map #(* % %)) (filter odd?))

step 5

  • js to select map and move it down once
(->> [1 2 3 4 5] (filter odd?) (map #(* % %))</span>)

step 6

  • C-f or C-3 to exit the list (l should work as well since the point is still special)
  • M to multiline
(->> [1 2 3 4 5]
     (filter odd?)
     (map #(* % %)))</span>