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TS JS Deno

Returns true if the given value is a number, false otherwise.

Use !isNaN() in combination with parseFloat() to check if the argument is a number. Use isFinite() to check if the number is finite. Use Number() to check if the coercion holds.

const validateNumber = (n: number | string) =>
!isNaN(parseFloat(n)) && isFinite(n) && Number(n) == n;
validateNumber("10"); // true