currying.js

/**
 * Curry - Function currying
 * Copyright (c) 2008 Ariel Flesler - aflesler(at)gmail(dot)com | http://flesler.blogspot.com
 * Licensed under BSD (http://www.opensource.org/licenses/bsd-license.php)
 * Date: 10/4/2008
 *
 * @author Ariel Flesler
 * @version 1.0.1
 */

function curry( fn ){
	return function(){
		var args = curry.args(arguments),
			master = arguments.callee,
			self = this;

		return args.length >= fn.length ? fn.apply(self,args) :	function(){
			return master.apply( self, args.concat(curry.args(arguments)) );
		};
	};
};

curry.args = function( args ){
	return Array.prototype.slice.call(args);
};

Function.prototype.curry = function(){
	return curry(this);
};

Curry by Ariel Flesler

Links
Download(1.0.1)
Haskell Functions
// Check http://demos.flesler.com/Curry/js/Curry.js for the curry() function  
// These are some examples of currying application  
// They were also executed so you can try them on a console  
  
// General  

function compose(f, g) {
	return function(x,y) {
		return g(f(y))(x); 
	}
}
function delegate(f) {
	return function(v) {
		f(v)
	}
}
// Math   
function sum(x){
	return function(y) {
		x + y;
	}
}
var inc = sum(1);  
inc(2) //3
var dec = sum(-1);  
dec(2) //1
   
function prod(x) {
	return function(y) {
		return x * y;
	}
}
var negate = prod(-1);        
var sub = compose(negate, sum);  
var inv = function( x ){  
    return 1/x;  
};  
var div = compose(inv, prod);  
  
// DOM        
function attr(elem, key) {
	return function(value) {
		elem[key] = value;  	
	}
}
var setCookie = attr(document,'cookie');  
setCookie('foo=bar;');  
  
// Arrays  
function each(f) {
	return function(l) {
		for( var i=0; i < list.length; i++ )  
        	f( list[i], i );  	
	}
}

var printAll = each(function(x){console.log(x);})

var map = curry(function( f, list ){  
    var copy = [];  
    each(function(e, i){  
        copy[i] = f(e);  
    }, list );  
    return copy;  
});  
function map(f) {
	return function(l) {
		var copy = [];  
    	each(function(e, i){  
        	copy[i] = f(e);  
    	}, l);  
    return copy;  	
	}
}

//XXX
var reduce = curry(function( f, accum, list ){  
    each(function( e ){  
        return accum = f( accum, e );  
    }, list );  
    return accum;  
});  

function reduce(f) {
	
	return function(accum, l) {  
		each(function( e ){  
        return accum = f( accum, e );  
    }, l );  
    return accum;  
	}
}

var printAll = reduce(function(acc,x) {console.log(x);})

printAll([1,2,3])

  
var sumAll = reduce(function(acc,x) {return acc + x;},0); 

sumAll([1,2,3])


// f.e: incAll( [1,2,3] ) --> [2,3,4]  
var incAll = map( inc );  
var decAll = map( dec );  
var doubleAll = map( prod(2) );  
var alertList = each( alert );  
var sumList = reduce( sum, 0 );  
var concat = reduce( sum, '' );  
var length = reduce( inc, 0 );