i've been localizing handles with anonymous subroutines for a while now.
i think i'd write your snippet as an anonymous sub, giving it a little more muscle compared to a do block. something like:
#!/usr/bin/perl
require 5.006_001;
use strict;
use warnings;
$|++;
my %cool_funcs = (
## slurp a file to a scalar
## pass filename (as scalar)
## returns contents of file (scalar context)
slurp_to_scalar => sub{ local( *ARGV, $/ ); @ARGV = @_; <> },
## slurp one or more files to an array
## pass filename(s) (as scalar)
## returns contents of file(s) (list context)
## returns number of lines (scalar context)
slurp_to_array => sub{ local *ARGV; @ARGV = @_; <> },
);
## to use it:
## create a list of test files
my @files = @ARGV;
## get the contents to an array, and the number of lines to a scalar
my $no_of_lines = ( my @contents ) =
$cool_funcs{slurp_to_array}->( @files );
## these values match...
print $no_of_lines, $/, scalar @contents, $/;
## here's the good stuff...
print @contents;
## get file to scalar -- note extra args are ignored
my $data = $cool_funcs{slurp_to_scalar}->( @files );
## here's the file's contents...
print $data;
~Particle *accelerates*