<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;">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.<br><br> --mr<br><br>================<br><br>[michael@localhost ~]$ ghci<br>GHCi, version 6.10.3: http://www.haskell.org/ghc/ :? for help<br>Loading package ghc-prim ... linking ... done.<br>Loading package integer ... linking ... done.<br>Loading package base ... linking ... done.<br>Prelude> if (1==1) then else<br><br><interactive>:1:15: parse error on input `else'<br>Prelude> if (1==1) then True else<br><br><interactive>:1:24: parse error (possibly incorrect indentation)<br>Prelude> if (1==1) then True else False<br>True<br>Prelude> <br><br></td></tr></table><br>