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+//>>built
+define("dojox/lang/functional/lambda", ["../..", "dojo/_base/kernel", "dojo/_base/lang", "dojo/_base/array"], function(dojox, dojo, lang, arr){
+ var df = lang.getObject("lang.functional", true, dojox);
+
+// This module adds high-level functions and related constructs:
+// - anonymous functions built from the string
+
+// Acknoledgements:
+// - lambda() is based on work by Oliver Steele
+// (http://osteele.com/sources/javascript/functional/functional.js)
+// which was published under MIT License
+
+// Notes:
+// - lambda() produces functions, which after the compilation step are
+// as fast as regular JS functions (at least theoretically).
+
+// Lambda input values:
+// - returns functions unchanged
+// - converts strings to functions
+// - converts arrays to a functional composition
+
+ var lcache = {};
+
+ // split() is augmented on IE6 to ensure the uniform behavior
+ var split = "ab".split(/a*/).length > 1 ? String.prototype.split :
+ function(sep){
+ var r = this.split.call(this, sep),
+ m = sep.exec(this);
+ if(m && m.index == 0){ r.unshift(""); }
+ return r;
+ };
+
+ var lambda = function(/*String*/ s){
+ var args = [], sects = split.call(s, /\s*->\s*/m);
+ if(sects.length > 1){
+ while(sects.length){
+ s = sects.pop();
+ args = sects.pop().split(/\s*,\s*|\s+/m);
+ if(sects.length){ sects.push("(function(" + args + "){return (" + s + ")})"); }
+ }
+ }else if(s.match(/\b_\b/)){
+ args = ["_"];
+ }else{
+ var l = s.match(/^\s*(?:[+*\/%&|\^\.=<>]|!=)/m),
+ r = s.match(/[+\-*\/%&|\^\.=<>!]\s*$/m);
+ if(l || r){
+ if(l){
+ args.push("$1");
+ s = "$1" + s;
+ }
+ if(r){
+ args.push("$2");
+ s = s + "$2";
+ }
+ }else{
+ // the point of the long regex below is to exclude all well-known
+ // lower-case words from the list of potential arguments
+ var vars = s.
+ replace(/(?:\b[A-Z]|\.[a-zA-Z_$])[a-zA-Z_$\d]*|[a-zA-Z_$][a-zA-Z_$\d]*:|this|true|false|null|undefined|typeof|instanceof|in|delete|new|void|arguments|decodeURI|decodeURIComponent|encodeURI|encodeURIComponent|escape|eval|isFinite|isNaN|parseFloat|parseInt|unescape|dojo|dijit|dojox|window|document|'(?:[^'\\]|\\.)*'|"(?:[^"\\]|\\.)*"/g, "").
+ match(/([a-z_$][a-z_$\d]*)/gi) || [], t = {};
+ arr.forEach(vars, function(v){
+ if(!(v in t)){
+ args.push(v);
+ t[v] = 1;
+ }
+ });
+ }
+ }
+ return {args: args, body: s}; // Object
+ };
+
+ var compose = function(/*Array*/ a){
+ return a.length ?
+ function(){
+ var i = a.length - 1, x = df.lambda(a[i]).apply(this, arguments);
+ for(--i; i >= 0; --i){ x = df.lambda(a[i]).call(this, x); }
+ return x;
+ }
+ :
+ // identity
+ function(x){ return x; };
+ };
+
+ lang.mixin(df, {
+ // lambda
+ rawLambda: function(/*String*/ s){
+ // summary:
+ // builds a function from a snippet, or array (composing),
+ // returns an object describing the function; functions are
+ // passed through unmodified.
+ // description:
+ // This method is to normalize a functional representation (a
+ // text snippet) to an object that contains an array of
+ // arguments, and a body , which is used to calculate the
+ // returning value.
+ return lambda(s); // Object
+ },
+ buildLambda: function(/*String*/ s){
+ // summary:
+ // builds a function from a snippet, returns a string, which
+ // represents the function.
+ // description:
+ // This method returns a textual representation of a function
+ // built from the snippet. It is meant to be evaled in the
+ // proper context, so local variables can be pulled from the
+ // environment.
+ s = lambda(s);
+ return "function(" + s.args.join(",") + "){return (" + s.body + ");}"; // String
+ },
+ lambda: function(/*Function|String|Array*/ s){
+ // summary:
+ // builds a function from a snippet, or array (composing),
+ // returns a function object; functions are passed through
+ // unmodified.
+ // description:
+ // This method is used to normalize a functional
+ // representation (a text snippet, an array, or a function) to
+ // a function object.
+ if(typeof s == "function"){ return s; }
+ if(s instanceof Array){ return compose(s); }
+ if(s in lcache){ return lcache[s]; }
+ s = lambda(s);
+ return lcache[s] = new Function(s.args, "return (" + s.body + ");"); // Function
+ },
+ clearLambdaCache: function(){
+ // summary:
+ // clears internal cache of lambdas
+ lcache = {};
+ }
+ });
+
+ return df;
+});