Hi, Larry Wall wrote: > : Same for hashes: [...] > : my %hash = (a => 1, b => 2), > : my $pair := %hash.pick; > : $pair = ...; # %hash changed > > I'm not sure that works. We don't quite have pairs as first class > containers. Binding would try to use a pair as a named argument, and > would fail unless the key happened to be 'pair', which it isn't in > this case.
Oh yes, of course. Others may be interested in http://groups.google.com/groups?threadm=x7wtsvo0fs.fsf%40mail.sysarch.com. > then it has a better chance of working, presuming someone has the > gumption to write .pick on hashes, which doesn't look entirely trivial > to do right. <thinking out loud>I'm sure I overlooked something, but the following seems to be correct and is not *that* difficult :): class Hash; ...; method pick() is rw { # First pick a random key. my $key = .keys.pick; # Then return an appropriate Proxy object: return new Proxy: FETCH => { Ok. While typing the C<{> here, I realized you were correct :) It'd be reasonable simple if there was a .get_pair_by_key method (which'd do appropriate binding and'd be C<is rw>): method pick() is rw { my $key = .keys.pick; my $pair := .get_pair_by_key($key); return $pair; } --Ingo -- Linux, the choice of a GNU | Mathematicians practice absolute freedom. generation on a dual AMD | -- Henry Adams Athlon! |
