Re: How to access a variable inside subroutine?

Some preamble:

Your 'use 5.030;' will give you an automatic 'use strict;' but not a 'use warnings;'. It would've been better to start with:

use 5.030;
use warnings;
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For the code you've posted, you only need 'use 5.010;' for state and say, see perl5100delta; and 'use 5.012;' to get the 'use strict;', see use.

In the following, I've used an alias of mine I commonly use for testing:

$ alias perle
alias perle='perl -Mstrict -Mwarnings -Mautodie=:all -MCarp::Always -E
+'
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and, my Perl version is 5.32.0:

$ perl -v | head -2 | tail -1
This is perl 5, version 32, subversion 0 (v5.32.0) built for cygwin-th
+read-multi
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Here's an example of what you could have done that makes sense of the use of state (using slightly easier to follow numbers):

$ perle '
    say counter() for 1..3;

    sub counter {
        state $add;
        $add += $_ for (1..5);
        return $add;
    }
'
15
30
45
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You could've also assigned the return value and used it later. This example also shows two $add variables, used in different lexical scopes, with no conflict.

$ perle '
    my $add;

    for (1..3) {
        $add = counter();
        say "... other processing here ...";
        say $add;
    }

    sub counter {
        state $add;
        $add += $_ for (1..5);
        return $add;
    }
'
... other processing here ...
15
... other processing here ...
30
... other processing here ...
45
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— Ken

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