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TS JS Deno

Checks if the given argument is a number.

Use typeof to check if a value is classified as a number primitive. To safeguard against NaN, check if val === val (as NaN has a typeof equal to number and is the only value not equal to itself).

const isNumber = (val: any) => typeof val === "number" && val === val;
isNumber(1); // true
isNumber("1"); // false
isNumber(NaN); // false