33 lines
924 B
TypeScript
33 lines
924 B
TypeScript
/*---------------------------------------------------------------------------------------------
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* Copyright (c) Microsoft Corporation. All rights reserved.
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* Licensed under the MIT License. See License.txt in the project root for license information.
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*--------------------------------------------------------------------------------------------*/
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export function startsWith(haystack: string, needle: string): boolean {
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if (haystack.length < needle.length) {
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return false;
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}
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for (let i = 0; i < needle.length; i++) {
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if (haystack[i] !== needle[i]) {
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return false;
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}
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}
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return true;
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}
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/**
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* Determines if haystack ends with needle.
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*/
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export function endsWith(haystack: string, needle: string): boolean {
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let diff = haystack.length - needle.length;
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if (diff > 0) {
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return haystack.lastIndexOf(needle) === diff;
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} else if (diff === 0) {
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return haystack === needle;
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} else {
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return false;
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}
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}
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