The Tor Browser: addon-sdk/source/lib/sdk/lang/functional.js@129ffea94266 (annotated)

addon-sdk/source/lib/sdk/lang/functional.js@129ffea94266 (annotated)

addon-sdk/source/lib/sdk/lang/functional.js

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 // Disclaimer: Some of the functions in this module implement APIs from
 // Jeremy Ashkenas's http://underscorejs.org/ library and all credits for
 // those goes to him.
 "use strict";
 module.metadata = {
   "stability": "unstable"
 };
 const { deprecateFunction } = require("../util/deprecate");
 const { setImmediate, setTimeout, clearTimeout } = require("../timers");
 const arity = f => f.arity || f.length;
 const name = f => f.displayName || f.name;
 const derive = (f, source) => {
   f.displayName = name(source);
   f.arity = arity(source);
   return f;
 };
 /**
  * Takes variadic numeber of functions and returns composed one.
  * Returned function pushes `this` pseudo-variable to the head
  * of the passed arguments and invokes all the functions from
  * left to right passing same arguments to them. Composite function
  * returns return value of the right most funciton.
  */
 const method = (...lambdas) => {
   return function method(...args) {
     args.unshift(this);
     return lambdas.reduce((_, lambda) => lambda.apply(this, args),
                           void(0));
   };
 };
 exports.method = method;
 /**
  * Takes a function and returns a wrapped one instead, calling which will call
  * original function in the next turn of event loop. This is basically utility
  * to do `setImmediate(function() { ... })`, with a difference that returned
  * function is reused, instead of creating a new one each time. This also allows
  * to use this functions as event listeners.
  */
 const defer = f => derive(function(...args) {
   setImmediate(invoke, f, args, this);
 }, f);
 exports.defer = defer;
 // Exporting `remit` alias as `defer` may conflict with promises.
 exports.remit = defer;
 /**
  * Invokes `callee` by passing `params` as an arguments and `self` as `this`
  * pseudo-variable. Returns value that is returned by a callee.
  * @param {Function} callee
  *    Function to invoke.
  * @param {Array} params
  *    Arguments to invoke function with.
  * @param {Object} self
  *    Object to be passed as a `this` pseudo variable.
  */
 const invoke = (callee, params, self) => callee.apply(self, params);
 exports.invoke = invoke;
 /**
  * Takes a function and bind values to one or more arguments, returning a new
  * function of smaller arity.
  *
  * @param {Function} fn
  *    The function to partial
  *
  * @returns The new function with binded values
  */
 const partial = (f, ...curried) => {
   if (typeof(f) !== "function")
     throw new TypeError(String(f) + " is not a function");
   let fn = derive(function(...args) {
     return f.apply(this, curried.concat(args));
   }, f);
   fn.arity = arity(f) - curried.length;
   return fn;
 };
 exports.partial = partial;
 /**
  * Returns function with implicit currying, which will continue currying until
  * expected number of argument is collected. Expected number of arguments is
  * determined by `fn.length`. Using this with variadic functions is stupid,
  * so don't do it.
  *
  * @examples
  *
  * var sum = curry(function(a, b) {
  *   return a + b
  * })
  * console.log(sum(2, 2)) // 4
  * console.log(sum(2)(4)) // 6
  */
 const curry = new function() {
   const currier = (fn, arity, params) => {
     // Function either continues to curry arguments or executes function
     // if desired arguments have being collected.
     const curried = function(...input) {
       // Prepend all curried arguments to the given arguments.
       if (params) input.unshift.apply(input, params);
       // If expected number of arguments has being collected invoke fn,
       // othrewise return curried version Otherwise continue curried.
       return (input.length >= arity) ? fn.apply(this, input) :
              currier(fn, arity, input);
     };
     curried.arity = arity - (params ? params.length : 0);
     return curried;
   };
   return fn => currier(fn, arity(fn));
 };
 exports.curry = curry;
 /**
  * Returns the composition of a list of functions, where each function consumes
  * the return value of the function that follows. In math terms, composing the
  * functions `f()`, `g()`, and `h()` produces `f(g(h()))`.
  * @example
  *
  *   var greet = function(name) { return "hi: " + name; };
  *   var exclaim = function(statement) { return statement + "!"; };
  *   var welcome = compose(exclaim, greet);
  *
  *   welcome('moe');    // => 'hi: moe!'
  */
 function compose(...lambdas) {
   return function composed(...args) {
     let index = lambdas.length;
     while (0 <= --index)
       args = [lambdas[index].apply(this, args)];
     return args[0];
   };
 }
 exports.compose = compose;
 /*
  * Returns the first function passed as an argument to the second,
  * allowing you to adjust arguments, run code before and after, and
  * conditionally execute the original function.
  * @example
  *
  *  var hello = function(name) { return "hello: " + name; };
  *  hello = wrap(hello, function(f) {
  *    return "before, " + f("moe") + ", after";
  *  });
  *
  *  hello();    // => 'before, hello: moe, after'
  */
 const wrap = (f, wrapper) => derive(function wrapped(...args) {
   return wrapper.apply(this, [f].concat(args));
 }, f);
 exports.wrap = wrap;
 /**
  * Returns the same value that is used as the argument. In math: f(x) = x
  */
 const identity = value => value;
 exports.identity = identity;
 /**
  * Memoizes a given function by caching the computed result. Useful for
  * speeding up slow-running computations. If passed an optional hashFunction,
  * it will be used to compute the hash key for storing the result, based on
  * the arguments to the original function. The default hashFunction just uses
  * the first argument to the memoized function as the key.
  */
 const memoize = (f, hasher) => {
   let memo = Object.create(null);
   let cache = new WeakMap();
   hasher = hasher || identity;
   return derive(function memoizer(...args) {
     const key = hasher.apply(this, args);
     const type = typeof(key);
     if (key && (type === "object" || type === "function")) {
       if (!cache.has(key))
         cache.set(key, f.apply(this, args));
       return cache.get(key);
     }
     else {
       if (!(key in memo))
         memo[key] = f.apply(this, args);
       return memo[key];
     }
   }, f);
 };
 exports.memoize = memoize;
 /**
  * Much like setTimeout, invokes function after wait milliseconds. If you pass
  * the optional arguments, they will be forwarded on to the function when it is
  * invoked.
  */
 const delay = function delay(f, ms, ...args) {
   setTimeout(() => f.apply(this, args), ms);
 };
 exports.delay = delay;
 /**
  * Creates a version of the function that can only be called one time. Repeated
  * calls to the modified function will have no effect, returning the value from
  * the original call. Useful for initialization functions, instead of having to
  * set a boolean flag and then check it later.
  */
 const once = f => {
   let ran = false, cache;
   return derive(function(...args) {
     return ran ? cache : (ran = true, cache = f.apply(this, args));
   }, f);
 };
 exports.once = once;
 // export cache as once will may be conflicting with event once a lot.
 exports.cache = once;
 // Takes a `f` function and returns a function that takes the same
 // arguments as `f`, has the same effects, if any, and returns the
 // opposite truth value.
 const complement = f => derive(function(...args) {
   return args.length < arity(f) ? complement(partial(f, ...args)) :
          !f.apply(this, args);
 }, f);
 exports.complement = complement;
 // Constructs function that returns `x` no matter what is it
 // invoked with.
 const constant = x => _ => x;
 exports.constant = constant;
 // Takes `p` predicate, `consequent` function and an optional
 // `alternate` function and composes function that returns
 // application of arguments over `consequent` if application over
 // `p` is `true` otherwise returns application over `alternate`.
 // If `alternate` is not a function returns `undefined`.
 const when = (p, consequent, alternate) => {
   if (typeof(alternate) !== "function" && alternate !== void(0))
     throw TypeError("alternate must be a function");
   if (typeof(consequent) !== "function")
     throw TypeError("consequent must be a function");
   return function(...args) {
     return p.apply(this, args) ?
            consequent.apply(this, args) :
            alternate && alternate.apply(this, args);
   };
 };
 exports.when = when;
 // Apply function that behaves as `apply` does in lisp:
 // apply(f, x, [y, z]) => f.apply(f, [x, y, z])
 // apply(f, x) => f.apply(f, [x])
 const apply = (f, ...rest) => f.apply(f, rest.concat(rest.pop()));
 exports.apply = apply;
 // Returns function identical to given `f` but with flipped order
 // of arguments.
 const flip = f => derive(function(...args) {
   return f.apply(this, args.reverse());
 }, f);
 exports.flip = flip;
 // Takes field `name` and `target` and returns value of that field.
 // If `target` is `null` or `undefined` it would be returned back
 // instead of attempt to access it's field. Function is implicitly
 // curried, this allows accessor function generation by calling it
 // with only `name` argument.
 const field = curry((name, target) =>
   // Note: Permisive `==` is intentional.
   target == null ? target : target[name]);
 exports.field = field;
 // Takes `.` delimited string representing `path` to a nested field
 // and a `target` to get it from. For convinience function is
 // implicitly curried, there for accessors can be created by invoking
 // it with just a `path` argument.
 const query = curry((path, target) => {
   const names = path.split(".");
   const count = names.length;
   let index = 0;
   let result = target;
   // Note: Permisive `!=` is intentional.
   while (result != null && index < count) {
     result = result[names[index]];
     index = index + 1;
   }
   return result;
 });
 exports.query = query;
 // Takes `Type` (constructor function) and a `value` and returns
 // `true` if `value` is instance of the given `Type`. Function is
 // implicitly curried this allows predicate generation by calling
 // function with just first argument.
 const isInstance = curry((Type, value) => value instanceof Type);
 exports.isInstance = isInstance;
 /*
  * Takes a funtion and returns a wrapped function that returns `this`
  */
 const chainable = f => derive(function(...args) {
   f.apply(this, args);
   return this;
 }, f);
 exports.chainable = chainable;
 exports.chain =
   deprecateFunction(chainable, "Function `chain` was renamed to `chainable`");
 // Functions takes `expected` and `actual` values and returns `true` if
 // `expected === actual`. Returns curried function if called with less then
 // two arguments.
 //
 // [ 1, 0, 1, 0, 1 ].map(is(1)) // => [ true, false, true, false, true ]
 const is = curry((expected, actual) => actual === expected);
 exports.is = is;
 const isnt = complement(is);
 exports.isnt = isnt;
 /**
  * From underscore's `_.debounce`
  * http://underscorejs.org
  * (c) 2009-2014 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
  * Underscore may be freely distributed under the MIT license.
  */
 const debounce = function debounce (fn, wait) {
   let timeout, args, context, timestamp, result;
   let later = function () {
     let last = Date.now() - timestamp;
     if (last < wait) {
       timeout = setTimeout(later, wait - last);
     } else {
       timeout = null;
       result = fn.apply(context, args);
       context = args = null;
     }
   };
   return function (...aArgs) {
     context = this;
     args = aArgs;
     timestamp  = Date.now();
     if (!timeout) {
       timeout = setTimeout(later, wait);
     }
     return result;
   };
 };
 exports.debounce = debounce;
 /**
  * From underscore's `_.throttle`
  * http://underscorejs.org
  * (c) 2009-2014 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
  * Underscore may be freely distributed under the MIT license.
  */
 const throttle = function throttle (func, wait, options) {
   let context, args, result;
   let timeout = null;
   let previous = 0;
   options || (options = {});
   let later = function() {
     previous = options.leading === false ? 0 : Date.now();
     timeout = null;
     result = func.apply(context, args);
     context = args = null;
   };
   return function() {
     let now = Date.now();
     if (!previous && options.leading === false) previous = now;
     let remaining = wait - (now - previous);
     context = this;
     args = arguments;
     if (remaining <= 0) {
       clearTimeout(timeout);
       timeout = null;
       previous = now;
       result = func.apply(context, args);
       context = args = null;
     } else if (!timeout && options.trailing !== false) {
       timeout = setTimeout(later, remaining);
     }
     return result;
   };
 };
 exports.throttle = throttle;