MIT licensed by Chris Martin
Maintained by Chris Martin, Julie Moronuki
This version can be pinned in stack with:d10-,4159
Used by 1 package in lts-19.7(full list with versions):

Data types representing the digits zero through nine.


Each of the following modules defines a different type named D10, all of which are different representations of the same concept:

  • D10.Char - Defines a D10 type as a newtype for Char, where the values are restricted to characters between '0' and '9'

  • D10.Num - Defines a D10 type as a newtype for any type with an instance of the Num class, where the values are restricted to numbers between fromInteger 0 and fromInteger 9

  • D10.Safe - Defines a D10 type as D0 | D1 | D2 | ... | D9

The Arithmetic modules provide infix operators (+), (-), (*) for modular arithmetic:

  • D10.Char.Arithmetic

  • D10.Num.Arithmetic

  • D10.Safe.Arithmetic

The following modules export constructors that can be used incorrectly:

  • D10.Char.Unsafe

  • D10.Num.Unsafe

Functions to test whether values of various types represent digits in the range 0 to 9:

  • D10.Predicate


  • The D10.Char and D10.Num modules include quasi-quoters named d10 used to express single digits. For example, 7 can be written as [d10|7|]. This is an important feature because the D10 types defined in these modules have unsafe constructors, and the quasi-quoters provide compile-time assurance that we never construct a D10 that represents a value outside the range 0 to 9.

  • D10.Char, D10.Num, and D10.Safe include quasi-quoters named d10list to express lists of digits. For example, [4, 5, 6] can be written as [d10list|456|].