Function currying

[jeffrose]

Unless I overlooked it, I did not see a utility to curry functions.

var slice = Array.prototype.slice;

/*
 * Create a function by partially invoking an existing function
 * 
 * var add = function( a, b ){
 *     return a + b;
 *   },
 * 
 *   addTen = curry( add, 10 );
 * 
 * add( 1, 2 ); //--> 3
 * addTen( 1 ); //--> 11
 */

return function( fn ){
    var args = slice.call( arguments, 1 );

    return function(){
        return fn.apply( this, args.concat( slice.call( arguments ) ) );
    };
};

[millermedeiros]

function/bind can be used for currying, the only difference is that it allows setting the context (this value). addTen = bind(add, this, 10). Do you think we should add a new method?

[jeffrose]

I saw bind but completely overlooked the fact it passed in arguments. That being the case, adding curry is more about convenience and syntax than adding real functionality. In fact I assume it would end up being implemented using bind.

There might be an argument that adding curry falls under the "be clear" goal since it could be argued that...

var addTen = curry( add, 10 );

... is more clear than...

var addTen = bind( add, this, 10 );

... but I don't feel that strongly about it because I think it is also reasonable to keep the API concise.

[millermedeiros]

uhm, I think we should add it. specially since with curry we would be able to change the context (this) during invocation (with bind that isn't possible).

[jeffrose]

I had not thought of that. I think that's a much better argument for adding it than simply being clear.