
21 Oct
2009
21 Oct
'09
8:43 p.m.
It looks like both the THEN and the ELSE in an IF expression must each have an expression. What's a graceful way to do nothing in either or both slots, kind of like the Fortran CONTINUE statement. --mr ================ [michael@localhost ~]$ ghci GHCi, version 6.10.3: http://www.haskell.org/ghc/ :? for help Loading package ghc-prim ... linking ... done. Loading package integer ... linking ... done. Loading package base ... linking ... done. Prelude> if (1==1) then else <interactive>:1:15: parse error on input `else' Prelude> if (1==1) then True else <interactive>:1:24: parse error (possibly incorrect indentation) Prelude> if (1==1) then True else False True Prelude>