40 lines
1.1 KiB
TypeScript
40 lines
1.1 KiB
TypeScript
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// (C) Copyright 2015 Moodle Pty Ltd.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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/**
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* Singleton with helper functions for time operations.
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*/
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export class CoreTime {
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/**
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* Wrap a function so that it is called only once.
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*
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* @param fn Function.
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* @return Wrapper that will call the underlying function only once.
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*/
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static once<T extends unknown[]>(fn: (...args: T) => unknown): (...args: T) => void {
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let called = false;
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return (...args: T) => {
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if (called) {
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return;
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}
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called = true;
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fn.apply(null, args);
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};
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}
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}
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