@@ -167,4 +167,35 @@ hello.apply(null, ['hey!']);
167167* second argument is an array of arguments
168168* in non-strict mode if first argument is null then it'll point at the global object
169169* ``` Function.prototype.call ``` is just syntactic sugar over apply
170- * call expects parameters as normal instead of an array
170+ * call expects parameters as normal parameter list instead of an array
171+ 172+ ## partial application
173+ 174+ * call a function with less than all of it's arguments
175+ * and return a function expecting the rest of the arguments
176+ * this transformation of function is called currying or schonfinkelizing
177+ * use when find yourself calling a function with same arguments
178+ 179+ ``` js
180+ function curriedAdd (x ,y ) {
181+ if (y === undefined ){
182+ return function (y ){
183+ return x+ y;
184+ }
185+ }
186+ return x + y;
187+ }
188+ 189+ // or with more general curry function
190+ function curry (fn ){
191+ var slice = Array .prototype .slice ; // needed because arguments is not a real Array?
192+ var storedArgs = slice .call (arguments , 1 );
193+ return function (){
194+ var newArgs = slice .call (arguments );
195+ var args = storedArgs .concat (newArgs);
196+ fn .apply (null , args);
197+ };
198+ }
199+ 200+ curry (add, 6 )(7 );
201+ ```
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