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+//>>built
+// wrapped by build app
+define("dojox/lang/functional/numrec", ["dijit","dojo","dojox","dojo/require!dojox/lang/functional/lambda,dojox/lang/functional/util"], function(dijit,dojo,dojox){
+dojo.provide("dojox.lang.functional.numrec");
+
+dojo.require("dojox.lang.functional.lambda");
+dojo.require("dojox.lang.functional.util");
+
+// This module provides recursion combinators:
+// - a simplified numeric linear recursion combinator.
+
+// Acknoledgements:
+// - recursion combinators are inspired by Manfred von Thun's article
+// "Recursion Theory and Joy"
+// (http://www.latrobe.edu.au/philosophy/phimvt/joy/j05cmp.html)
+
+// Notes:
+// - recursion combinators produce a function, which implements
+// their respective recusion patterns. String lambdas are inlined, if possible.
+
+(function(){
+ var df = dojox.lang.functional, inline = df.inlineLambda,
+ _r_i = ["_r", "_i"];
+
+ df.numrec = function(/*Object*/ then, /*Function|String|Array*/ after){
+ // summary:
+ // Generates a function for the simplified numeric linear recursion pattern.
+ // All parameter functions are called in the context of "this" object.
+ // description:
+ // This is a simplification of the linear recursion combinator:
+ // - the generated function takes one numeric parameter "x",
+ // - the "cond" is fixed and checks for 0.
+ // - the "before" is fixed and the generated function is called with "x - 1".
+ // - the "above is called with two parameters: the return from the generated
+ // function, and with "x".
+ // - as you can see the recursion is done by decreasing the parameter,
+ // and calling itself until it reaches 0.
+ // then:
+ // The value, which is used upon termination of the recursion.
+ // It will be returned as the value of the generated function.
+ // above:
+ // The lambda expression, which is called after the recursive step.
+ // It accepts two parameters: the returned value from the recursive step, and
+ // the original parameter. The returned value will be returned as the value of
+ // the generated function.
+
+ var a, as, dict = {},
+ add2dict = function(x){ dict[x] = 1; };
+ if(typeof after == "string"){
+ as = inline(after, _r_i, add2dict);
+ }else{
+ a = df.lambda(after);
+ as = "_a.call(this, _r, _i)";
+ }
+ var locals = df.keys(dict),
+ f = new Function(["_x"], "var _t=arguments.callee,_r=_t.t,_i".concat( // Function
+ locals.length ? "," + locals.join(",") : "",
+ a ? ",_a=_t.a" : "",
+ ";for(_i=1;_i<=_x;++_i){_r=",
+ as,
+ "}return _r"
+ ));
+ f.t = then;
+ if(a){ f.a = a; }
+ return f;
+ };
+})();
+
+/*
+For documentation only:
+
+1) The original recursive version:
+
+var numrec1 = function(then, after){
+ var after = df.lambda(after);
+ return function(x){
+ return x ? after.call(this, arguments.callee.call(this, x - 1), x) : then;
+ };
+};
+
+2) The original iterative version (before minification and inlining):
+
+var numrec2 = function(then, after){
+ var after = df.lambda(after);
+ return function(x){
+ var ret = then, i;
+ for(i = 1; i <= x; ++i){
+ ret = after.call(this, ret, i);
+ }
+ return ret;
+ };
+};
+
+*/
+});