lodash: added _.flow() and _.flowRight() (aliases: _.backflow(), _.compose())

lodash/lodash-tests.ts

@@ -754,6 +754,12 @@ _.forEach(saves, function (type) {
     asyncSave({ 'type': type, 'complete': done });
 });
 
+// _.backflow
+var testBackflowSquareFn = (n: number) => n * n;
+var testBackflowAddFn = (n: number, m: number) => n + m;
+result = <number>_.backflow<(n: number, m: number) => number>(testBackflowSquareFn, testBackflowAddFn)(1, 2);
+result = <number>_(testBackflowSquareFn).backflow<(n: number, m: number) => number>(testBackflowAddFn).value()(1, 2);
+
 var funcBind = function(greeting: string, punctuation: string) { return greeting + ' ' + this.user + punctuation; };
 var funcBound1: (punctuation: string) => any = _.bind(funcBind, { 'name': 'moe' }, 'hi');
 funcBound1('!');
@@ -795,21 +801,11 @@ funcBindKey();
 funcBindKey = _(objectBindKey).bindKey('greet', 'hi').value();
 funcBindKey();
 
-var realNameMap: { [index: string]: string; } = {
-    'curly': 'jerome'
-};
-
-var format = function (name: string) {
-    name = realNameMap[name.toLowerCase()] || name;
-    return name.charAt(0).toUpperCase() + name.slice(1).toLowerCase();
-};
-
-var greet = function (formatted: string) {
-    return 'Hiya ' + formatted + '!';
-};
-
-result = <Function>_.compose(greet, format);
-result = <_.LoDashObjectWrapper<Function>>_(greet).compose(format);
+// _.compose
+var testComposeSquareFn = (n: number) => n * n;
+var testComposeAddFn = (n: number, m: number) => n + m;
+result = <number>_.compose<(n: number, m: number) => number>(testComposeSquareFn, testComposeAddFn)(1, 2);
+result = <number>_(testComposeSquareFn).compose<(n: number, m: number) => number>(testComposeAddFn).value()(1, 2);
 
 var createCallbackObj: { [index: string]: string; } = { name: 'Joe' };
 result = <() => any>_.createCallback('name');
@@ -858,6 +854,18 @@ var log = _.bind(console.log, console);
 result = <number>_.delay(log, 1000, 'logged later');
 result = <_.LoDashWrapper<number>>_(log).delay(1000, 'logged later');
 
+// _.flow
+var testFlowSquareFn = (n: number) => n * n;
+var testFlowAddFn = (n: number, m: number) => n + m;
+result = <number>_.flow<(n: number, m: number) => number>(testFlowAddFn, testFlowSquareFn)(1, 2);
+result = <number>_(testFlowAddFn).flow<(n: number, m: number) => number>(testFlowSquareFn).value()(1, 2);
+
+// _.flowRight
+var testFlowRightSquareFn = (n: number) => n * n;
+var testFlowRightAddFn = (n: number, m: number) => n + m;
+result = <number>_.flowRight<(n: number, m: number) => number>(testFlowRightSquareFn, testFlowRightAddFn)(1, 2);
+result = <number>_(testFlowRightSquareFn).flowRight<(n: number, m: number) => number>(testFlowRightAddFn).value()(1, 2);
+
 var fibonacci = <Function>_.memoize(function (n: any): number {
     return n < 2 ? n : fibonacci(n - 1) + fibonacci(n - 2);
 });

lodash/lodash.d.ts

@@ -5183,6 +5183,21 @@ declare module _ {
         after(func: Function): LoDashObjectWrapper<Function>;
     }
 
+    //_.backflow
+    interface LoDashStatic {
+        /**
+         * @see _.flowRight
+         */
+        backflow<TResult extends Function>(...funcs: Function[]): TResult;
+    }
+
+    interface LoDashObjectWrapper<T> {
+        /**
+         * @see _.flowRight
+         **/
+        backflow<TResult extends Function>(...funcs: Function[]): LoDashObjectWrapper<TResult>;
+    }
+
     //_.bind
     interface LoDashStatic {
         /**
@@ -5261,21 +5276,16 @@ declare module _ {
     //_.compose
     interface LoDashStatic {
         /**
-        * Creates a function that is the composition of the provided functions, where each function
-        * consumes the return value of the function that follows. For example, composing the functions
-        * f(), g(), and h() produces f(g(h())). Each function is executed with the this binding of the
-        * composed function.
-        * @param funcs Functions to compose.
-        * @return The new composed function.
-        **/
-        compose(...funcs: Function[]): Function;
+         * @see _.flowRight
+         */
+        compose<TResult extends Function>(...funcs: Function[]): TResult;
     }
 
     interface LoDashObjectWrapper<T> {
         /**
-        * @see _.compose
-        **/
-        compose(...funcs: Function[]): LoDashObjectWrapper<Function>;
+         * @see _.flowRight
+         */
+        compose<TResult extends Function>(...funcs: Function[]): LoDashObjectWrapper<TResult>;
     }
 
     //_.createCallback
@@ -5442,6 +5452,42 @@ declare module _ {
             ...args: any[]): LoDashWrapper<number>;
     }
 
+    //_.flow
+    interface LoDashStatic {
+        /**
+         * Creates a function that returns the result of invoking the provided functions with the this binding of the
+         * created function, where each successive invocation is supplied the return value of the previous.
+         * @param funcs Functions to invoke.
+         * @return Returns the new function.
+         */
+        flow<TResult extends Function>(...funcs: Function[]): TResult;
+    }
+
+    interface LoDashObjectWrapper<T> {
+        /**
+         * @see _.flow
+         **/
+        flow<TResult extends Function>(...funcs: Function[]): LoDashObjectWrapper<TResult>;
+    }
+
+    //_.flowRight
+    interface LoDashStatic {
+        /**
+         * This method is like _.flow except that it creates a function that invokes the provided functions from right
+         * to left.
+         * @param funcs Functions to invoke.
+         * @return Returns the new function.
+         */
+        flowRight<TResult extends Function>(...funcs: Function[]): TResult;
+    }
+
+    interface LoDashObjectWrapper<T> {
+        /**
+         * @see _.flowRight
+         **/
+        flowRight<TResult extends Function>(...funcs: Function[]): LoDashObjectWrapper<TResult>;
+    }
+
     //_.memoize
     interface LoDashStatic {
         /**