Create a gist now

Instantly share code, notes, and snippets.

What would you like to do?
parse indentation of string

This function returns an array of the indentation level of each line of a string.

I made this as part of a yaml parser I'm trying to do =D

you use it like this:

getIndent("\t\t\ttext\n\tmore text\nnot indented")

and it returns this:


for(a in b=a.split("\n")) //for each line
b[a]=/\t*/.exec(b[a])[0].length; //replace string with indentation level
return b //return the array
function(a,b){for(a in b=a.split("\n"))b[a]=/\t*/.exec(b[a])[0].length;return b}
//@maettig's version
function(a,b){b=[];a.replace(/^\t*/gm,function(c){b.push(c.length)});return b}
"name": "getIndent",
"description": "Returns an array of the indentation level of each line of a string.",
"keywords": [
<!DOCTYPE html>
<b id=foo></b>
foo = document.getElementById("foo")
getIndent = function(a,b){for(a in b=a.split("\n"))b[a]=/\t*/.exec(b[a])[0].length;return b}
foo.innerHTML = getIndent("\t\t\ttext\n\tmore text\nnot indented")

tsaniel commented May 21, 2012

Save 2 bytes:
function(a,b,i){b=[];for(i in a=a.split("\n"))b[i]=/\t*/.exec(a[i])[0].length;return b}

atk commented May 21, 2012

Save 5 more bytes by reusing variables:

function(a,b){for(a in b=a.split("\n"))b[a]=/\t*/.exec(b[a])[0].length;return b}


williammalo commented May 21, 2012

@tsaniel ah thanks!
@atk Smart! Thanks!

maettig commented May 24, 2012

I tried to come up with my own solution and ended with something 2 bytes smaller. This abuses replace like it's a loop. Edit: Also it's a bit more reliable since your version returns [1] instead of [0] for "a\t".

function(a,b){b=[];a.replace(/^\t*/gm,function(c){b.push(c.length)});return b}

williammalo commented May 24, 2012

ah! very cool!

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment