All,

Background: What got me thinking

As has been discussed recently:

my $persist if 0; # illegal >= 5.10.0
[download]

Is an unusual construct which effectively creates a state variable due to the weird way perl handles lexicals (compile and runtime). It has been argued, that my should never be used with a postfix conditional. That is probably a good idea even when you only want a lexical to be created if some other condition is true. An if block should be used for that.

Actual Question: (see this also)

My question has to do with the following unrelated construct:

if (my $result = some_func()) {
    # do something with $result
}
[download]

There are a couple of reasons you might want to do this:

• You want $result scoped as small as possible
• The some_func() is impure and subsequent calls will change the results

This leaves a few questions for me.

• Is there any sane alternative that satisfies the two reasons above?
• Is the implicit scoping of $result to the if block going to continue to work in Perl 6

To be honest, I really don't care as I can count the number of times I have used that construct on one hand. I ask because the recent state discussions have made me wonder if Perl 6 is going to clean up all the cobwebs in the corners.

Questions Answered

Update: Feel free to continue to contribute if you have something to add, but my questions have been answered - see here, here, and here

Update: Added a couple of headings

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