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+if(!dojo._hasResource["dojox.lang.functional.fold"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
+dojo._hasResource["dojox.lang.functional.fold"] = true;
+dojo.provide("dojox.lang.functional.fold");
+
+dojo.require("dojox.lang.functional.lambda");
+
+// This module adds high-level functions and related constructs:
+// - "fold" family of functions
+
+// Notes:
+// - missing high-level functions are provided with the compatible API:
+// foldl, foldl1, foldr, foldr1
+// - missing JS standard functions are provided with the compatible API:
+// reduce, reduceRight
+
+// Defined methods:
+// - take any valid lambda argument as the functional argument
+// - operate on dense arrays
+// - take a string as the array argument
+// - take an iterator objects as the array argument (only foldl, foldl1, and reduce)
+
+(function(){
+ var d = dojo, df = dojox.lang.functional;
+
+ d.mixin(df, {
+ // classic reduce-class functions
+ foldl: function(/*Array|String|Object*/ a, /*Function*/ f, /*Object*/ z, /*Object?*/ o){
+ // summary: repeatedly applies a binary function to an array from left
+ // to right using a seed value as a starting point; returns the final
+ // value.
+ if(typeof a == "string"){ a = a.split(""); }
+ o = o || d.global; f = df.lambda(f);
+ if(d.isArray(a)){
+ for(var i = 0, n = a.length; i < n; z = f.call(o, z, a[i], i, a), ++i);
+ }else{
+ for(var i = 0; a.hasNext(); z = f.call(o, z, a.next(), i++));
+ }
+ return z; // Object
+ },
+ foldl1: function(/*Array|String|Object*/ a, /*Function|String|Array*/ f, /*Object?*/ o){
+ // summary: repeatedly applies a binary function to an array from left
+ // to right; returns the final value.
+ if(typeof a == "string"){ a = a.split(""); }
+ o = o || d.global; f = df.lambda(f);
+ var z;
+ if(d.isArray(a)){
+ z = a[0];
+ for(var i = 1, n = a.length; i < n; z = f.call(o, z, a[i], i, a), ++i);
+ }else if(a.hasNext()){
+ z = a.next();
+ for(var i = 1; a.hasNext(); z = f.call(o, z, a.next(), i++));
+ }
+ return z; // Object
+ },
+ foldr: function(/*Array|String*/ a, /*Function|String|Array*/ f, /*Object*/ z, /*Object?*/ o){
+ // summary: repeatedly applies a binary function to an array from right
+ // to left using a seed value as a starting point; returns the final
+ // value.
+ if(typeof a == "string"){ a = a.split(""); }
+ o = o || d.global; f = df.lambda(f);
+ for(var i = a.length; i > 0; --i, z = f.call(o, z, a[i], i, a));
+ return z; // Object
+ },
+ foldr1: function(/*Array|String*/ a, /*Function|String|Array*/ f, /*Object?*/ o){
+ // summary: repeatedly applies a binary function to an array from right
+ // to left; returns the final value.
+ if(typeof a == "string"){ a = a.split(""); }
+ o = o || d.global; f = df.lambda(f);
+ var n = a.length, z = a[n - 1];
+ for(var i = n - 1; i > 0; --i, z = f.call(o, z, a[i], i, a));
+ return z; // Object
+ },
+ // JS 1.8 standard array functions, which can take a lambda as a parameter.
+ reduce: function(/*Array|String|Object*/ a, /*Function*/ f, /*Object?*/ z){
+ // summary: apply a function simultaneously against two values of the array
+ // (from left-to-right) as to reduce it to a single value.
+ return arguments.length < 3 ? df.foldl1(a, f) : df.foldl(a, f, z); // Object
+ },
+ reduceRight: function(/*Array|String*/ a, /*Function*/ f, /*Object?*/ z){
+ // summary: apply a function simultaneously against two values of the array
+ // (from right-to-left) as to reduce it to a single value.
+ return arguments.length < 3 ? df.foldr1(a, f) : df.foldr(a, f, z); // Object
+ }
+ });
+})();
+
+}