On 2016-02-08 17:24, wizard wrote:
Dear all,
I just started to learn Haskell with learnyouahaskell.com and at the very beginning, I met a strange issue with following simple function:
-- why does work with "toZero 10" but not for "toZero -10"? toZero :: (Integral t) => t -> [t]
[..]
This function works as expected for positive arguments, e.g., "toZero 10" gives me [10,9,8,7,6,5,4,3,2,1,0]. However, GHCI will raise following error if I give it a negative argument, e.g., "toZero -10":
[..] The issue is that 'toZero -10' is parsed as 'toZero minus 10', i.e. it's not a negative value you're passing there. It expects 'toZero' to be a numeric value. Try toZero (-10) instead. -- Frerich Raabe - raabe@froglogic.com www.froglogic.com - Multi-Platform GUI Testing