26 Feb
2009
26 Feb
'09
9:47 a.m.
On Thursday 26 February 2009 5:36:05 am Christian Maeder wrote:
Libraries-List,
browsing through the sources of Data.List I discovered "select", which is only used for the implementation of partition and not exported.
Can someone explain, why the irrefutable pattern "~" is used? Both components are used in both branches.
To see the difference, go into ghci, and define select without the irrefutable pattern. Then run the following: foldr (select even) ([],[]) [1..]