parseNumberOrBigInt

parseNumberOrBigInt(text): number | bigint | null

Defined in: packages/core/src/number/parse-number-or-big-int.ts:31

Parse a numeric literal, widening to bigint rather than rounding.

An integer the double range cannot hold exactly comes back as a bigint, so no value is silently rounded; everything else comes back as a number, so a caller only ever meets a bigint where it changes the answer.

Accepts what BigInt() accepts — an optional sign, decimal digits, and the 0b/0o/0x prefixes — and otherwise what Number() accepts: a fractional part, an exponent, and Infinity. Surrounding whitespace is ignored by both. Blank text is null here, where Number("") answers 0.

Use this to read a number out of text a human wrote — an environment variable, a config field, a CLI argument. Prefer bigIntParse when the value must be an integer, or when the radix is known and not spelled in the text; it reports a malformed input by throwing instead of by returning null.

Parameters

text

string

The text to parse.

Returns

number | bigint | null

The number or bigint it spells, or null if it spells neither.

Example

  parseNumberOrBigInt("42"); // 42
  parseNumberOrBigInt("1.5e3"); // 1500
  parseNumberOrBigInt("9007199254740993"); // 9007199254740993n
  parseNumberOrBigInt("abc"); // null
  ```;