# Data.String

parsePositive : Num a => String -> Maybe a

  Convert a positive number string to a Num.

      parsePositive "123"

      parsePositive {a=Int} " +123"

parseInteger : Num a => Neg a => String -> Maybe a

  Convert a number string to a Num.

      parseInteger " 123"

      parseInteger {a=Int} " -123"

parseDouble : String -> Maybe Double

  Convert a number string to a Double.

      parseDouble "+123.123e-2"

      parseDouble {a=Int} " -123.123E+2"

      parseDouble {a=Int} " +123.123"