Function fromString

packages/effect/src/BigDecimal.ts:894–937

(s: string)

 * @category constructors
 */
export const fromString = (s: string): Option.Option<BigDecimal> => {
  if (s === "") {
    return Option.some(zero)
  }

  let base: string
  let exp: number
  const seperator = s.search(/[eE]/)
  if (seperator !== -1) {
    const trail = s.slice(seperator + 1)
    base = s.slice(0, seperator)
    exp = Number(trail)
    if (base === "" || !Number.isSafeInteger(exp) || !FINITE_INT_REGEX.test(trail)) {
      return Option.none()
    }
  } else {
    base = s
    exp = 0
  }

  let digits: string
  let offset: number
  const dot = base.search(/\./)
  if (dot !== -1) {
    const lead = base.slice(0, dot)
    const trail = base.slice(dot + 1)
    digits = `${lead}${trail}`
    offset = trail.length
  } else {
    digits = base
    offset = 0
  }

  if (!FINITE_INT_REGEX.test(digits)) {
    return Option.none()
  }

  const scale = offset - exp
  if (!Number.isSafeInteger(scale)) {
    return Option.none()
  }

  return Option.some(make(BigInt(digits), scale))
}

/**
 * Parses a numerical `string` into a `BigDecimal`.