On Thu, Oct 16, 2008 at 10:37:41PM +0200, Eirik Berg Hanssen wrote: : [EMAIL PROTECTED] writes: : : > -C<< infix:<where> >>, sequential junctional and operator : > +C<< infix:<also> >>, sequential junctional and operator : > : > - EXPR where EXPR where EXPR ... : > + EXPR also EXPR also EXPR ... : > : > Can be used to construct ANDed patterns with the same semantics as : > C<< infix:<&> >>, but with left-to-right evaluation guaranteed, for use : > in guarded patterns: : > : > - $target ~~ MyType where .mytest1 where .mytest2 : > + $target ~~ MyType also .mytest1 also .mytest2 : > : > This is useful when later tests might throw exceptions if earlier : > tests don't pass. This cannot be guaranteed by: : : All this, just to get the exceptions in the right order?
It's to get exceptions not to happen at all. Normal junctions don't trap exceptions either, but also can't guarantee order of evaluation. This variant does. That's all. Larry
