Hi, Any thoughts about what to do about this?

If I understand, lexical subs can not currently be used with recursion which re-enters the scope where the lexical sub is defined, because the recursive call will not create a new closure (or not properly). Is that right?

If there is no solution possible, then it might be best to document the limitation in perlsub.

#!/usr/bin/env perl
use strict; use warnings; use feature qw/say state/;
STDOUT->autoflush; STDERR->autoflush;
say "Perl version $^V";

sub process($;$) {
  my ($value, $callback) = @_;
  say "### process($value,", ($callback//"undef"), ")";

  my sub inner {
    if ($callback) {
      return $callback->($value+1);
    } else {
      return $value+1;
    }
  }

  inner();
}

my $result =
  process(1, sub{
                 my $arg = shift;
                 say "#   callback called with arg $arg";
                 process($arg+100);
              });
say "result=", ($result//"undef");

#  Perl version v5.36.0
#  ### process(1,CODE(0x555555971f10))
#  #   callback called with arg 2
#  Can't undef active subroutine at /tmp/t line 25.

Can't undef active subroutine #18606

Description

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

Issue actions