sub outer {
   my ($param) = @_;

   local *inner1 = sub {
      ...
   };

   local *inner2 = sub {
      ...
   };

   ...

   inner2(inner1($param));
}
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hey you name them, they are not anonymous! ; )

This trick with local is nice! 8 )

But without trying it, I'll expect that you'll vivify global entries in the symbol table. (which are of course empty after the local scope ended)

I'd rather prefer this construction

my $inner1_cr=sub {...} ;
$inner_cr->($param);
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Cheers Rolf

hey you name them, they are not anonymous! ; )

Not when its compiled, and that makes a difference.

>perl -c -we"sub outer { my $x; sub inner { $x } inner() }"
Variable "$x" will not stay shared at -e line 1.
-e syntax OK

>perl -c -we"sub outer { my $x; local *inner = sub { $x }; inner() }"
-e syntax OK
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And yeah, it's effectively a named sub thereafter. That's a bonus.

I'd rather prefer this construction

I usually use inner subs for recursive functions, and my would cause a memory leak there. It also needlessly complicates the calling syntax.

sub outer {
  ...
  my $helper;
  $helper = sub {      # $helper references helper sub
     ...
     $helper->();      # helper sub references $helper
     ...
  };
  ...
}
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Cyclic reference ⇒ memory leak.

use strict;
use warnings;

print join "\n", myBigSub (1 .. 10);

sub myBigSub {
    my @params = &myLittleSub1;
    @params = myLittleSub4 (myLittleSub3 (myLittleSub2 (@params)));
    @params = myLittleSub5 (@params);
    return @params;
}


sub myLittleSub1 {
    my (@params) = @_;
    return reverse @params;
}


sub myLittleSub2 {
    return map {$_ * 3} @_;
}


sub myLittleSub3 {
    my @params = grep {$_ % 6} @_;
    return @params;
}


sub myLittleSub4 {
    my @params = @_;
    return @params[1, 2, 4];
}


sub myLittleSub5 {
    my (@params) = @_;

    $_ = 'x' x $_ for @params;
    return @params;
}
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Prints:

xxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxx
xxx
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use strict;
use warnings;

sub FirstSub {
    my ($Param) = @_;

    sub add1 {my ($arg)=@_; return $arg+1;};
    sub add2 {my ($arg)=@_; return $arg+2;};
    sub add3 {my ($arg)=@_; return $arg+3;};
    sub add4 {my ($arg)=@_; return $arg+4;};
    sub add5 {my ($arg)=@_; return $arg+5;};

    $Param = add1($Param);
    $Param = add2($Param);
    $Param = add3($Param);
    $Param = add4($Param);
    $Param = add5($Param);

    return $Param;
}

print FirstSub(10);
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