Function isLength

Checks if a given value is a valid length.

A valid length is of type number, is a non-negative integer, and is less than or equal to JavaScript's maximum safe integer (Number.MAX_SAFE_INTEGER). It returns true if the value is a valid length, and false otherwise.

This function can also serve as a type predicate in TypeScript, narrowing the type of the argument to a valid length (number).

isLength(0); // true
isLength(42); // true
isLength(-1); // false
isLength(1.5); // false
isLength(Number.MAX_SAFE_INTEGER); // true
isLength(Number.MAX_SAFE_INTEGER + 1); // false
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