55 lines
973 B
Plaintext
55 lines
973 B
Plaintext
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/**
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* Simple memoize
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* wxs doesn't support fn.apply, so this memoize only support up to 2 args
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*/
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function isPrimitive(value) {
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var type = typeof value;
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return (
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type === 'boolean' ||
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type === 'number' ||
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type === 'string' ||
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type === 'undefined' ||
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value === null
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);
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}
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// mock simple fn.call in wxs
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function call(fn, args) {
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if (args.length === 2) {
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return fn(args[0], args[1]);
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}
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if (args.length === 1) {
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return fn(args[0]);
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}
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return fn();
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}
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function serializer(args) {
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if (args.length === 1 && isPrimitive(args[0])) {
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return args[0];
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}
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var obj = {};
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for (var i = 0; i < args.length; i++) {
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obj['key' + i] = args[i];
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}
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return JSON.stringify(obj);
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}
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function memoize(fn) {
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var cache = {};
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return function() {
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var key = serializer(arguments);
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if (cache[key] === undefined) {
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cache[key] = call(fn, arguments);
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}
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return cache[key];
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};
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}
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module.exports.memoize = memoize;
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