is_decimal_integer_token Function

public pure function is_decimal_integer_token(token) result(valid)

符号付き十進整数tokenだけを許可する。

Arguments

Type IntentOptional Attributes Name
character(len=*), intent(in) :: token

Return Value logical


Source Code

  pure logical function is_decimal_integer_token(token) result(valid)
    character(len=*), intent(in) :: token
    integer :: position, token_length

    valid = .false.
    token_length = len_trim(token)
    if (token_length <= 0) return
    position = 1
    if (token(position:position) == '+' .or. token(position:position) == '-') position = position + 1
    if (position > token_length) return
    do while (position <= token_length)
      if (.not. is_decimal_digit(token(position:position))) return
      position = position + 1
    end do
    valid = .true.
  end function is_decimal_integer_token