issue#25 - Implement Function.prototype.bind()

Author: ashishdutta050

implementations/bind.js

@@ -0,0 +1,27 @@
+
+// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_objects/Function/bind
+
+/*
+  Bind function returns a new bounded function and passes the "this" reference to be used by the targeted function
+  The bind() function creates a new bound function, which is an exotic function object
+  that wraps the original function object.
+*/
+
+Function.prototype.altBind = function (someObj, ...outerFuncArguments1) {
+  const targetFunc = this;
+
+  // return inner function
+  return function (...innerFuncArgs1) {
+
+    let propKey = Math.random().toString();
+    while (someObj.hasOwnProperty(propKey)) {
+      propKey = Math.random().toString();
+    }
+    someObj[propKey] = targetFunc;
+
+    // prepend outer args to inner args
+    const result = someObj[propKey](...outerFuncArguments1, ...innerFuncArgs1);
+    delete someObj[propKey];
+    return result;
+  }
+}