A Chrome snipet for http://drboolean.gitbooks.io/mostly-adequate-guide/

functional-snipets.js

// -- Base -- //

// original from https://gist.github.com/amatiasq/2e4344792f28611fa499
function curry(fn, length) {
  length = length || fn.length;
  return function currified() {
    var args = [].slice.call(arguments);

    if (args.length === 0)
      return currified;

    if (args.length >= length)
      return fn.apply(this, args);

    var child = fn.bind.apply(fn, [this].concat(args));
    return curry(child, length - args.length);
  };
}

// original from https://github.com/jashkenas/underscore/blob/master/underscore.js#L884

var compose = function() {
    var args = arguments;
    var start = args.length - 1;
    return function() {
        var i = start;
        var result = args[start].apply(this, arguments);
        while (i--) {
            result = args[i].call(this, result);
        }
        return result;
    };
};

var id = function(x){ return x; };

// -- Utilities -- //

var trace = curry(function(tag, x){
  console.log(tag, x);
  return x;
});

// -- Numbers -- //

var add = curry(function(a, b){
    return a + b;
});

// -- Strings -- //

var split = curry(function split(divider, str){
    return str.split(divider);
});

var toLower = function toLower(str){
    return str.toLowerCase();
};

var replace = curry(function split(replacement, replacer, str){
    return str.replace(replacement, replacer);
});


var match = curry(function(reg, str){
  return reg.test(str);
});

// -- Arrays -- //

var head = function(x) { return x[0]; };

var last = function(x) { return x[x.length - 1]; };

var join = curry(function curry(glue, arr){
    return arr.join(glue);
})

var map = curry(function map(fn, arr){
  return arr.map(fn);
});

var filter = curry(function(fn, arr){
  return arr.filter(fn);
});

var reduce = curry(function(fn, initval, arr){
    return arr.reduce(fn, initval);
});

var slice = curry(function(start, end, arr){
    return arr.slice(start, end);
});

// -- Objects -- //

var prop = curry(function prop(prop, obj){
    return obj[prop];
})