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1 | define("dojo/AdapterRegistry", ["./_base/kernel", "./_base/lang"], function(dojo, lang) { |
2 | // module: | |
3 | // dojo/AdapterRegistry | |
4 | // summary: | |
5 | // TODOC | |
6 | ||
7 | var AdapterRegistry = dojo.AdapterRegistry = function(/*Boolean?*/ returnWrappers){ | |
8 | // summary: | |
9 | // A registry to make contextual calling/searching easier. | |
10 | // description: | |
11 | // Objects of this class keep list of arrays in the form [name, check, | |
12 | // wrap, directReturn] that are used to determine what the contextual | |
13 | // result of a set of checked arguments is. All check/wrap functions | |
14 | // in this registry should be of the same arity. | |
15 | // example: | |
16 | // | // create a new registry | |
17 | // | var reg = new dojo.AdapterRegistry(); | |
18 | // | reg.register("handleString", | |
19 | // | dojo.isString, | |
20 | // | function(str){ | |
21 | // | // do something with the string here | |
22 | // | } | |
23 | // | ); | |
24 | // | reg.register("handleArr", | |
25 | // | dojo.isArray, | |
26 | // | function(arr){ | |
27 | // | // do something with the array here | |
28 | // | } | |
29 | // | ); | |
30 | // | | |
31 | // | // now we can pass reg.match() *either* an array or a string and | |
32 | // | // the value we pass will get handled by the right function | |
33 | // | reg.match("someValue"); // will call the first function | |
34 | // | reg.match(["someValue"]); // will call the second | |
35 | ||
36 | this.pairs = []; | |
37 | this.returnWrappers = returnWrappers || false; // Boolean | |
38 | }; | |
39 | ||
40 | /*===== | |
41 | // doc alias helpers: | |
42 | AdapterRegistry = dojo.AdapterRegistry; | |
43 | =====*/ | |
44 | ||
45 | lang.extend(AdapterRegistry, { | |
46 | register: function(/*String*/ name, /*Function*/ check, /*Function*/ wrap, /*Boolean?*/ directReturn, /*Boolean?*/ override){ | |
47 | // summary: | |
48 | // register a check function to determine if the wrap function or | |
49 | // object gets selected | |
50 | // name: | |
51 | // a way to identify this matcher. | |
52 | // check: | |
53 | // a function that arguments are passed to from the adapter's | |
54 | // match() function. The check function should return true if the | |
55 | // given arguments are appropriate for the wrap function. | |
56 | // directReturn: | |
57 | // If directReturn is true, the value passed in for wrap will be | |
58 | // returned instead of being called. Alternately, the | |
59 | // AdapterRegistry can be set globally to "return not call" using | |
60 | // the returnWrappers property. Either way, this behavior allows | |
61 | // the registry to act as a "search" function instead of a | |
62 | // function interception library. | |
63 | // override: | |
64 | // If override is given and true, the check function will be given | |
65 | // highest priority. Otherwise, it will be the lowest priority | |
66 | // adapter. | |
67 | this.pairs[((override) ? "unshift" : "push")]([name, check, wrap, directReturn]); | |
68 | }, | |
69 | ||
70 | match: function(/* ... */){ | |
71 | // summary: | |
72 | // Find an adapter for the given arguments. If no suitable adapter | |
73 | // is found, throws an exception. match() accepts any number of | |
74 | // arguments, all of which are passed to all matching functions | |
75 | // from the registered pairs. | |
76 | for(var i = 0; i < this.pairs.length; i++){ | |
77 | var pair = this.pairs[i]; | |
78 | if(pair[1].apply(this, arguments)){ | |
79 | if((pair[3])||(this.returnWrappers)){ | |
80 | return pair[2]; | |
81 | }else{ | |
82 | return pair[2].apply(this, arguments); | |
83 | } | |
84 | } | |
85 | } | |
86 | throw new Error("No match found"); | |
87 | }, | |
88 | ||
89 | unregister: function(name){ | |
90 | // summary: | |
91 | // Remove a named adapter from the registry | |
92 | // name: String | |
93 | // The name of the adapter. | |
94 | // returns: Boolean | |
95 | // Returns true if operation is successful. | |
96 | // Returns false if operation fails. | |
97 | ||
98 | // FIXME: this is kind of a dumb way to handle this. On a large | |
99 | // registry this will be slow-ish and we can use the name as a lookup | |
100 | // should we choose to trade memory for speed. | |
101 | for(var i = 0; i < this.pairs.length; i++){ | |
102 | var pair = this.pairs[i]; | |
103 | if(pair[0] == name){ | |
104 | this.pairs.splice(i, 1); | |
105 | return true; | |
106 | } | |
107 | } | |
108 | return false; | |
109 | } | |
110 | }); | |
111 | ||
112 | return AdapterRegistry; | |
113 | }); |