26 lines
729 B
JavaScript
26 lines
729 B
JavaScript
//#region src/predicate/isNull.ts
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/**
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* Checks if the given value is null.
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*
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* This function tests whether the provided value is strictly equal to `null`.
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* It returns `true` if the value is `null`, and `false` otherwise.
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*
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* This function can also serve as a type predicate in TypeScript, narrowing the type of the argument to `null`.
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*
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* @param x - The value to test if it is null.
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* @returns True if the value is null, false otherwise.
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*
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* @example
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* const value1 = null;
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* const value2 = undefined;
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* const value3 = 42;
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*
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* console.log(isNull(value1)); // true
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* console.log(isNull(value2)); // false
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* console.log(isNull(value3)); // false
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*/
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function isNull(x) {
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return x === null;
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}
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//#endregion
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exports.isNull = isNull;
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