9 Dec
2004
9 Dec
'04
8:58 p.m.
numLines :: [Line] -> [(Int, Line)] numLines lines -- list of pairs of = zip [1 .. length lines] lines -- line no. & line
zip stops when it reaches the end of the shorter list, so you can just say zip [1 ..] lines In fact, most programmers use the infix version of zip, like this: [1..] `zip` lines which is nicely readable. (any function can be turned into an infix by surrounding it in `backticks`). --KW 8-) -- Keith Wansbrough <kw217@cl.cam.ac.uk> http://www.cl.cam.ac.uk/users/kw217/ University of Cambridge Computer Laboratory.