43 lines
1.1 KiB
JavaScript
43 lines
1.1 KiB
JavaScript
// Reference counter, useful for garbage collector like functionality
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"use strict";
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var d = require("d")
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, extensions = require("../lib/registered-extensions")
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, create = Object.create
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, defineProperties = Object.defineProperties;
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extensions.refCounter = function (ignore, conf, options) {
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var cache, postfix;
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cache = create(null);
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postfix =
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(options.async && extensions.async) || (options.promise && extensions.promise)
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? "async"
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: "";
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conf.on("set" + postfix, function (id, length) { cache[id] = length || 1; });
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conf.on("get" + postfix, function (id) { ++cache[id]; });
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conf.on("delete" + postfix, function (id) { delete cache[id]; });
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conf.on("clear" + postfix, function () { cache = {}; });
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defineProperties(conf.memoized, {
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deleteRef: d(function () {
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var id = conf.get(arguments);
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if (id === null) return null;
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if (!cache[id]) return null;
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if (!--cache[id]) {
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conf.delete(id);
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return true;
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}
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return false;
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}),
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getRefCount: d(function () {
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var id = conf.get(arguments);
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if (id === null) return 0;
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if (!cache[id]) return 0;
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return cache[id];
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}),
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});
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};
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