work

Author: iliakan

1-js/3-object-basics/8-iterable/article.md

@@ -132,7 +132,7 @@ while(true) {
 
 The same works for an array.
 
-## Iterables VS array-likes
+## Iterables VS array-likes [#array-like]
 
 There are two official terms that are similar, but actually very different. Please take care to avoid the confusion.
 

1-js/7-deeper/6-call-apply-decorators/1-delay/_js.view/solution.js

@@ -0,0 +1,7 @@
+function delay(f, ms) {
+
+  return function() {
+    setTimeout(() => f.apply(this, arguments), ms);
+  };
+
+};

1-js/7-deeper/6-call-apply-decorators/1-delay/_js.view/test.js

@@ -0,0 +1,46 @@
+describe("delay", function() {
+  before(function() {
+    this.clock = sinon.useFakeTimers();
+  });
+
+  after(function() {
+    this.clock.restore();
+  });
+
+  it("вызывает функцию через указанный таймаут", function() {
+    var start = Date.now();
+
+    function f(x) {
+      assert.equal(Date.now() - start, 1000);
+    }
+    f = sinon.spy(f);
+
+    var f1000 = delay(f, 1000);
+    f1000("test");
+    this.clock.tick(2000);
+    assert(f.calledOnce, 'calledOnce check fails');
+  });
+
+  it("передаёт аргументы и контекст", function() {
+    var start = Date.now();
+    var user = {
+      sayHi: function(phrase, who) {
+        assert.equal(this, user);
+        assert.equal(phrase, "Привет");
+        assert.equal(who, "Вася");
+        assert.equal(Date.now() - start, 1500);
+      }
+    };
+
+    user.sayHi = sinon.spy(user.sayHi);
+
+    var spy = user.sayHi;
+    user.sayHi = delay(user.sayHi, 1500);
+
+    user.sayHi("Привет", "Вася");
+
+    this.clock.tick(2000);
+
+    assert(spy.calledOnce, 'проверка calledOnce не сработала');
+  });
+});

1-js/7-deeper/6-call-apply-decorators/1-delay/solution.md

@@ -0,0 +1,26 @@
+
+
+```js run
+function delay(f, ms) {
+
+*!*
+  return function() {
+    setTimeout(() => f.apply(this, arguments), ms);
+  };
+*/!*
+
+}
+
+function f(x) {
+  alert(x);
+}
+
+let f1000 = delay(f, 1000);
+let f1500 = delay(f, 1500);
+
+f1000("test"); // shows "test" after 1000ms
+f1500("test"); // shows "test" after 1500ms
+```
+
+Arrow function makes it easy, because `setTimeout` uses arguments and context of the wrapper .
+

1-js/7-deeper/6-call-apply-decorators/1-delay/task.md

@@ -0,0 +1,27 @@
+importance: 5
+
+---
+
+# Delaying decorator [todo move after arrow]
+
+Create a decorator `delay(f, ms)` that delays each call of `f` by `ms` milliseconds.
+
+For instance:
+
+```js
+function f(x) {
+  alert(x);
+}
+
+// create wrappers
+let f1000 = delay(f, 1000);
+let f1500 = delay(f, 1500);
+
+f1000("test"); // shows "test" after 1000ms
+f1500("test"); // shows "test" after 1500ms
+```
+
+In other words, `delay(f, ms)` returns a "delayed by `ms`" variant of `f`.
+
+In the code above, `f` is a function of a single argument, but your solution should pass all arguments and the context `this`.
+