Defining javascript prototype functions through a loop -


this question has answer here:

i try define prototype functions array. in following example : black rabbit should 'toto' doesn't ! why ?

function rabbit ( type ) {     this.type = type ; }  var funcs = ["says", "doesnt_say"];  for(var i=0;i<funcs.length;i++) {     var f = funcs[i];     rabbit.prototype[f] = function ( line ) {         alert(" " + this.type + " rabbit "                + f + "  '" + line + " '") ;     }; }  var blackrabbit = new rabbit ("black") ; blackrabbit.says("toto");

visible on http://jsfiddle.net/xou11bgu/

the problem variable "f" shared functions create, , end having value of last function name.

you can use function construct functions:

rabbit.prototype[f] = function(f) {     return function ( line ) {         alert(" " + this.type + " rabbit "                + f + "  '" + line + " '") ;     }; }(f);

this instance of extremely common javascript stumbling block; there many, many other similar questions here on stackoverflow, they're hard find because until know problem it's hard know you're looking for.


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