On Sat, Oct 26, 2002 at 11:24:23AM +0100, Nicholas Clark wrote: > On Sat, Oct 26, 2002 at 01:59:46AM +0200, Paul Johnson wrote: > > On Fri, Oct 25, 2002 at 06:28:28PM -0400, Miko O'Sullivan wrote: > > > From: "Larry Wall" <[EMAIL PROTECTED]> > > > > : ? - force to bool context > > > > : ! - force to bool context, negate > > > > : + - force to numeric context > > > > : - - force to numeric context, negate > > > > : ~ - force to string context > > > > > > > > We're obviously missing the "force to string context, negate" operator. > > > :-) > > > > > > Mr. Wall, may I be excused? My brain is full. Oh, I have to stick it out > > > with everyone else? OK, um.... > > > > > > Just so I understand... why do we need "force to blah context" operators at > > > all? Are we planning on doing a lot of context forcing? Isn't "a lot of > > > The negate operators we have already: > > > > perl -e '$x = "0"; print !$x' > > perl -e '$x = "10.000"; print -$x' > > Here is something that maybe you'd forgotten: > > $ perl -lwe '$x = "Good"; print -$x' > -Good > $ perl -lwe '$x = "-Good"; print -$x' > +Good > $ perl -lwe '$x = -"Good"; print -$x' > +Good > $ perl -lwe '$x = "+Good"; print -$x' > -Good > > Unary plus is actually irrelevant: > > $ perl -lwe '$x = +"Good"; print -$x' > -Good
I hadn't actually forgotton - I even re-read "Symbolic Unary Operators" in perlop, but I didn't want to wander too far off into strange Perl 5 territory. Miko actually wrote at the end of his mesage: ] -Miko ] uh oh, I just forced myself into numeric context and negated myself $ perl -lwe 'my $x = -Miko; print -$x' +Miko $ perl -lwe 'my $x = +Miko; print -$x' -Miko $ perl -Mstrict -lwe 'my $x = -Miko; print -$x' +Miko $ perl -Mstrict -lwe 'my $x = +Miko; print -$x' Bareword "Miko" not allowed while "strict subs" in use at -e line 1. Execution of -e aborted due to compilation errors. I know why that is, at least technically, but didn't fancy trying to explain why it should be like that from a language design point of view. Although I'm sure someone here could do that ;-) -- Paul Johnson - [EMAIL PROTECTED] http://www.pjcj.net
