Perl: cmpthese text vs anonymous sub problems with parameters passed -

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if read cmpthese in perl benchmark module's documentation, states cmpthese or timethese can used code in either text or subroutine references. documentation seems imply these forms interchangeable: 

# use perl code in strings... timethese($count, { 'name1' => '...code1...', 'name2' => '...code2...', }); # ... or use subroutine references. timethese($count, { 'name1' => sub { ...code1... }, 'name2' => sub { ...code2... }, });

i having difficulties passed parameters string form versus subroutine references form cmpthese. either values in @array not passed or have run-time error.

i have following code:

#!/usr/bin/perl use strict; use warnings; use benchmark qw(:all);  @array = qw( first second third );  sub target {     $str =  $_[0];     print "str=$str\n"; }  sub control {     print "control: array[0]=$array[0]\n"; }  $sub_ref=\⌖ $control_ref=\&control;  print "\n\n\n";  # error: array not passed... cmpthese(1, {     'target text' => 'target(@array)',     'control 1' => 'control()',  });  # ok... cmpthese(1, {     'sub code ref' => sub { target(@array) },     'control 2' => sub { control() }, });  # ok too... cmpthese(1, {     'target sub' => sub { $sub_ref->(@array) },     'control 3' => sub { $control_ref->() }, });  # fixed paramenters work: cmpthese(1, {     'target text fixed' => 'target("one", "two", "three")',     'control 4' => 'control()',  });  # run time error... cmpthese(1, {     'text code ref' => '$sub_ref->(@array)',     'control 5' => '$control_ref->()', });

all forms have work correctly eval think may issue benchmark? have used google foo try , find documented difference between 2 forms cannot.

does know reason simple examples above not seem work expected? comments in code indicate problems having on os x, perl 5.10.0.

i haven't looked in detail @ this, guess when benchmark evals strings code, lexical variable @array not in scope. things work if made @array our variable.

but in general, find easier use code refs.


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