Query string parsing

annotated.js

function(
	a, // the query string
	b, // placeholder
	c, // placeholder
	d, // placeholder
	e  // placeholder
) {
	for(
		b = /[?&]?([^=]+)=([^&]*)/g, // Create the regular expression to match key-value pairs.
		c = {},			     // Create the object to store all the key-value pairs.
		e = decodeURIComponent;	     // Alias the decodeURIComponent function to save bytes.
		d = b.exec(a.replace(/\+/g, ' '));
		c[e(d[1])] = e(d[2]) // store in the object.
	);
	
	return c; // return the object with the keys and pairs.
}

index.js

function(a,b,c,d,e){for(b=/[?&]?([^=]+)=([^&]*)/g,c={},e=decodeURIComponent;d=b.exec(a.replace(/\+/g,' '));c[e(d[1])]=e(d[2]));return c;}

LICENSE.txt

            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
                    Version 2, December 2004

 Copyright (C) 2011 Grant Butler

 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.

package.json

{
  "name": "query_string",

  "description": "Parses a query string and returns key-pairs as in object.",

  "keywords": [
    "query string",
    "query",
    "url" 
  ]
}

variant-annotated.js

function e(
	a, // The name of the key that we want the value for.
	b, // Placeholder
	c  // Placeholder
) {
	if(e.a == []._)   // Check if we e.a, where we store the object, exists.
		for(      // If not, we go into this for loop to create it.
			b = /[?&]?([^=]+)=([^&]*)/g, // Setup the RegEx. 
			e.a = {};		      // Initialize e.a.
			c = b.exec(location.search);    // Execute the RegEx.
			e.a[c[1]]=c[2]		      // Assign the pair.
		);

	return e.a[a]; // Return the value for the provided key.
}

variant.js

function e(a,b,c){if(e.a==[]._)for(b=/\??([^=]+)=([^&]+)&?/g,e.a={};c=b.exec(location.search);e.a[c[1]]=c[2]);return e.a[a];}

You could put the [?&] inside the expression part for the parameter key: instead of /[?&]?([^=]+)=([^&]*)/g, you could use /([^=?&]+)=([^&]*)/g, since those characters are not allowed unencoded within those keys anyway.

failed when test "?a=1&b=2#c"