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jed/LICENSE.txt

Forked from 140bytes/LICENSE.txt
Created September 7, 2011 13:30
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adler32 checksum
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index.js
function(a){for(var b=65521,c=1,d=0,e=0,f;f=a.charCodeAt(e++);d=(d+c)%b)c=(c+f)%b;return d<<16|c}
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LICENSE.txt
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004
Copyright (C) 2011 Jed Schmidt <http://jed.is>
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. You just DO WHAT THE FUCK YOU WANT TO.
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package.json
{
"name": "adler32",
"description": "a javascript port of wikipedia's example C implementation of Adler32",
"keywords": [
"checksum",
"hash",
"adler32"
]
}
Raw
test.html
<!DOCTYPE html>
<title>Foo</title>
<div>Expected value: <b>1802963080</b></div>
<div>Actual value: <b id="ret"></b></div>
<script>
var adler32 = function(a){for(var b=65521,c=1,d=0,e=0,f;f=a.charCodeAt(e++);d=(d+c)%b)c=(c+f)%b;return d<<16|c}
document.getElementById( "ret" ).innerHTML = adler32("140byt.es is totally rad!")
</script>
@subzey
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subzey commented Sep 7, 2011

@jed, Nice one!

Placeholder arguments aren't panacea for js minification, straightforward var declaration is 2 bytes shorter:

function(a){for(var b=65521,c=1,d=0,e=0,f;f=a.charCodeAt(e++);d=(d+c)%b)c=(c+f)%b;return(d<<16)|c}

@jed
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jed commented Sep 7, 2011

great point, @subzey, and very easy to forget. i'll fix this on the fletcher too.

EDIT: actually, it looks like fletcher doesn't need it.

@p01
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p01 commented Sep 7, 2011

Also, return c|d<<16 is 1 byte shorter

@jed
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jed commented Sep 7, 2011

thanks again, @p01!

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