7 Jul
2010
7 Jul
'10
1:54 p.m.
Patrick LeBoutillier wrote:
is there... perhaps a builtin function to flip a pair: (a, b) -> (b, a)
The function swap (x, y) = (y, x) will be added to Data.Tuple in the next release of the base libraries. In the meantime, it is easy enough to define it yourself, and then, of course rlookup x = lookup x . map swap Or, you could use the find function from Data.List and write: rlookup x = find ((== x) . snd) Regards, Yitz