60 lines
2.5 KiB
JavaScript
60 lines
2.5 KiB
JavaScript
const require_toArray = require("../_internal/toArray.js");
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const require_iteratee = require("../util/iteratee.js");
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const require_isArrayLikeObject = require("../predicate/isArrayLikeObject.js");
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const require_identity = require("../function/identity.js");
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const require_negate = require("../function/negate.js");
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//#region src/compat/array/takeWhile.ts
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/**
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* Creates a slice of the array with elements taken from the beginning while the specified predicate is satisfied.
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* If no predicate is provided, the identity function is used by default.
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* If the array is `null` or `undefined`, returns an empty array.
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*
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* @template T
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* @param {ArrayLike<T> | null | undefined} array - The array to process.
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* @param {(item: T, index: number, array: T[]) => unknown | Partial<T> | [keyof T, unknown] | PropertyKey} [predicate] - The condition used to determine elements to include. Can be:
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* - A function invoked per iteration.
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* - A partial object to match properties.
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* - A key-value pair as a tuple.
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* - A property key to check for truthy values.
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* Defaults to the identity function if not provided.
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* @returns {T[]} - A slice of the array with elements taken from the beginning or an empty array if `array` is `null` or `undefined`.
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*
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* @example
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* // Using a predicate function
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* const items = [1, 2, 3, 4, 5];
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* const result = takeWhile(items, (item) => item < 3);
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* console.log(result); // [1, 2]
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*
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* // Using a partial object
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* const items2 = [{ id: 30 }, { id: 20 }, { id: 10 }];
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* const result2 = takeWhile(items2, { id: 30 });
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* console.log(result2); // [{ id: 30 }]
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*
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* // Using a key-value pair
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* const items3 = [{ name: 'Alice' }, { name: 'Bob' }, { name: 'Alice' }];
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* const result3 = takeWhile(items3, ['name', 'Alice']);
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* console.log(result3); // [{ name: 'Alice' }]
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*
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* // Using a property key
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* const items4 = [{ active: true }, { active: true }, { active: false }];
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* const result4 = takeWhile(items4, 'active');
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* console.log(result4); // [{ active: true }, { active: true }]
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*
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* // No predicate provided
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* const items5 = [true, false];
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* const result5 = takeWhile(items5);
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* console.log(result5); // [true]
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*
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* // null or undefined array
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* const result6 = takeWhile(null);
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* console.log(result6); // []
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**/
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function takeWhile(array, predicate) {
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if (!require_isArrayLikeObject.isArrayLikeObject(array)) return [];
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const _array = require_toArray.toArray(array);
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const index = _array.findIndex(require_negate.negate(require_iteratee.iteratee(predicate ?? require_identity.identity)));
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return index === -1 ? _array : _array.slice(0, index);
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}
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//#endregion
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exports.takeWhile = takeWhile;
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