Re^2: What about if (my $var = foo()) { ... }

friedo,
Off hand, I can't think of any reason why this would not also be allowed in Perl 6.

In perl 5, we write:

for my $name (keys %people) {
    # do something with $name
}
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The $name lexical is implicitly scoped to the for block. This is not the case in perl 6. The way perl 6 solves this is by introducing parameters to the block so you achieve the same thing in a cleaner way (from a design perspective).

Cheers - L~R

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Re^3: What about if (my $var = foo()) { ... } by dsheroh (Monsignor) on Dec 29, 2007 at 16:39 UTC
Eh? Going away? What's the corresponding Perl 6 construct and how/why is it considered to be "cleaner"?	[reply]
Re^4: What about if (my $var = foo()) { ... } by Limbic~Region (Chancellor) on Dec 29, 2007 at 16:49 UTC
esper, See Re: What about if (my $var = foo()) { ... } for the Perl 6 construct. Regarding an explanation as to why formal parameters to a block are cleaner, it is similar to subs with and without signatures. If that still doesn't make any sense, I will try again when I am well rested. Cheers - L~R	[reply]
Re^5: What about if (my $var = foo()) { ... } by dsheroh (Monsignor) on Dec 29, 2007 at 18:46 UTC
Thanks for the pointer. I haven't been following Perl 6 at all, so some of the new syntax I'm seeing in Synopsis 4 is still a bit unclear, but I'm pretty sure I've at least got the formal parameters bit worked out. Personally, I think it looks less obvious/consistent than the existing Perl 5 equivalent (use `my` to create lexicals in some situations, use `->` or `^` in others) for the small benefit of eliminating implicit scopes, but I can easily see how others would disagree, given the number of complaints I've seen about subs always starting with a bunch of `my`s and `shift`s.	[reply] [d/l] [select]