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Function: fromString()

fromString(input): Result<number, ParseError>

Defined in: number/fromString/index.ts:35

Parses a string into a number.

Returns Ok with the parsed number, or Err with ParseError if parsing fails. Handles common number formats including decimals, negatives, and scientific notation.

Parameters​

input​

string

The string to parse

Returns​

Result<number, ParseError>

Result containing the parsed number or an error

Example​

fromString("123") // => Ok(123)
fromString("123.45") // => Ok(123.45)
fromString("-42") // => Ok(-42)
fromString("1.23e4") // => Ok(12300)
fromString("abc") // => Err({ code: 'PARSE_ERROR', ... })
fromString("") // => Err({ code: 'PARSE_ERROR', ... })

// Real-world: Form input validation
const validatePrice = (input: string) =>
  pipe(
    fromString(input),
    flatMap(price =>
      price > 0 ? ok(price) : err({ code: 'INVALID_PRICE' })
    )
  )

See​

fromCurrency - for parsing currency strings