
5 Dec
2008
5 Dec
'08
12:01 p.m.
Jules Bean schrieb:
Dmitri O.Kondratiev wrote:
I am trying to define instance Show[MyType] so show (x:xs :: MyType) would return a single string where substrings corresponding to list elements will be separated by "\n". This would allow pretty printing of MyType list in several lines instead of one, as default Show does for lists.
You're doing it wrong.
Show is not for pretty-printing.
(+1)
Show is for the production of haskell syntax for debugging and copy-pasting into test cases, as well as for use with 'Read'.
If you want to pretty print, use a different function name.
Maybe related: http://www.haskell.org/haskellwiki/List_instance