e44a7e37b6
git-svn-id: https://semanticscuttle.svn.sourceforge.net/svnroot/semanticscuttle/trunk@151 b3834d28-1941-0410-a4f8-b48e95affb8f
110 lines
3.7 KiB
JavaScript
110 lines
3.7 KiB
JavaScript
if(!dojo._hasResource["dojox.lang.functional.lambda"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
|
|
dojo._hasResource["dojox.lang.functional.lambda"] = true;
|
|
dojo.provide("dojox.lang.functional.lambda");
|
|
|
|
// 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
|
|
|
|
(function(){
|
|
var df = dojox.lang.functional;
|
|
|
|
// 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) || [];
|
|
var t = {};
|
|
dojo.forEach(vars, function(v){
|
|
if(!(v in t)){
|
|
args.push(v);
|
|
t[v] = 1;
|
|
}
|
|
});
|
|
}
|
|
}
|
|
return {args: args, body: "return (" + 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; };
|
|
};
|
|
|
|
dojo.mixin(df, {
|
|
// lambda
|
|
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(",") + "){" + 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); }
|
|
s = lambda(s);
|
|
return new Function(s.args, s.body); // Function
|
|
}
|
|
});
|
|
})();
|
|
|
|
}
|