var a = b = function( c ){ return c; };
//here, you can use a === b because they're pointing to the same memory and they're the same type
var a = function( c ){ return c; },
b = function( c ){ return c; };
//here you can use that byte-saver Andy E used (which is implicitly converting the function to it's body's text as a String),
''+a == ''+b.
//this is the gist of what is happening behind the scences:
a.toString( ) == b.toString( )