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Diffstat (limited to 'includes/js/dojox/lang/functional/curry.js')
-rw-r--r-- | includes/js/dojox/lang/functional/curry.js | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/includes/js/dojox/lang/functional/curry.js b/includes/js/dojox/lang/functional/curry.js new file mode 100644 index 0000000..7c795ec --- /dev/null +++ b/includes/js/dojox/lang/functional/curry.js @@ -0,0 +1,96 @@ +if(!dojo._hasResource["dojox.lang.functional.curry"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code. +dojo._hasResource["dojox.lang.functional.curry"] = true; +dojo.provide("dojox.lang.functional.curry"); + +dojo.require("dojox.lang.functional.lambda"); + +// This module adds high-level functions and related constructs: +// - currying and partial functions +// - argument pre-processing: mixer and flip + +// Acknoledgements: +// - partial() is based on work by Oliver Steele +// (http://osteele.com/sources/javascript/functional/functional.js) +// which was published under MIT License + +// Defined methods: +// - take any valid lambda argument as the functional argument + +(function(){ + var df = dojox.lang.functional; + + var currying = function(/*Object*/ info){ + return function(){ // Function + if(arguments.length + info.args.length < info.arity){ + return currying({func: info.func, arity: info.arity, + args: Array.prototype.concat.apply(info.args, arguments)}); + } + return info.func.apply(this, Array.prototype.concat.apply(info.args, arguments)); + }; + }; + + dojo.mixin(df, { + // currying and partial functions + curry: function(/*Function|String|Array*/ f, /*Number?*/ arity){ + // summary: curries a function until the arity is satisfied, at + // which point it returns the calculated value. + f = df.lambda(f); + arity = typeof arity == "number" ? arity : f.length; + return currying({func: f, arity: arity, args: []}); // Function + }, + arg: {}, // marker for missing arguments + partial: function(/*Function|String|Array*/ f){ + // summary: creates a function where some arguments are bound, and + // some arguments (marked as dojox.lang.functional.arg) are will be + // accepted by the final function in the order they are encountered. + // description: This method is used to produce partially bound + // functions. If you want to change the order of arguments, use + // dojox.lang.functional.mixer() or dojox.lang.functional.flip(). + var a = arguments, args = new Array(a.length - 1), p = []; + f = df.lambda(f); + for(var i = 1; i < a.length; ++i){ + var t = a[i]; + args[i - 1] = t; + if(t == df.arg){ + p.push(i - 1); + } + } + return function(){ // Function + var t = Array.prototype.slice.call(args, 0); // clone the array + for(var i = 0; i < p.length; ++i){ + t[p[i]] = arguments[i]; + } + return f.apply(this, t); + }; + }, + // argument pre-processing + mixer: function(/*Function|String|Array*/ f, /*Array*/ mix){ + // summary: changes the order of arguments using an array of + // numbers mix --- i-th argument comes from mix[i]-th place + // of supplied arguments. + f = df.lambda(f); + return function(){ // Function + var t = new Array(mix.length); + for(var i = 0; i < mix.length; ++i){ + t[i] = arguments[mix[i]]; + } + return f.apply(this, t); + }; + }, + flip: function(/*Function|String|Array*/ f){ + // summary: changes the order of arguments by reversing their + // order. + f = df.lambda(f); + return function(){ // Function + // reverse arguments + var a = arguments, l = a.length - 1, t = new Array(l + 1), i; + for(i = 0; i <= l; ++i){ + t[l - i] = a[i]; + } + return f.apply(this, t); + }; + } + }); +})(); + +} |