"Format STDOUT redefined"

sweetblood has asked for the wisdom of the Perl Monks concerning the following question:

I'm writing a script that uses "format STDOUT" in two seperate functions. But when I run the script I get the following error:

Format STDOUT redefined at ...

This happens even if the functions are not called.
I've done some looking around to find the answer. I read the perldoc perlform but it didn't quite sink in. Apparently my head is more dense than the perldoc. I'm guessing I need to use select somehow, but I just can't figure it out.
The script and even these functions are quite long so I'll include something I just dummied up that produces the same error:

#!/usr/bin/perl -w
use strict;
my $foo = "FOO";
my $bar = "BAR";
my $foobar = "FOOBAR";
sub foo {
    format STDOUT =
FOO      BAR
@<<<<<<< @<<<<<<<
$foo, $bar
.
    write;
}

sub foobar {
    format STDOUT =
FOOBAR BAR
@<<<<< @<<<<<<<
$foobar, $bar
.
    write;
}

foo() if ($ARGV[0] =~ /^foo$/i);
foobar() if ($ARGV[0] =~ /^foobar$/i);
[download]

I know this example isn't pretty but I just slammed it together.

TIA

Comment on "Format STDOUT redefined" Download Code

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Re: "Format STDOUT redefined" by Roy Johnson (Monsignor) on Dec 12, 2003 at 17:43 UTC
`format` is a compile-time global declaration.You can declare formats of different names and use the `$~` variable to pick which to write to in each subroutine. Or, as the Camel suggests, `use Filehandle` and call the `format_name` method on the handle as appropriate. The PerlMonk `tr///` Advocate	[reply]
Re: "Format STDOUT redefined" by Paladin (Vicar) on Dec 12, 2003 at 17:40 UTC
You can give your formats different names, and open FILEHANDLES with those names to STDOUT then use those names as parameters to `write`. ie: `open FORM1, ">-" or die "Error: $!\n"; open FORM2, ">-" or die "Error: $!\n"; format FORM1 = FOO BAR @<<<<<<< @<<<<<<< $foo, $bar . format FORM2 = FOOBAR BAR @<<<<< @<<<<<<< $foobar, $bar . write FORM1; write FORM2;` [download]	[reply] [d/l] [select]
Re: "Format STDOUT redefined" by ysth (Canon) on Dec 12, 2003 at 18:33 UTC
Since only one will be used, you could just wrap your formats in eval "". Or use IO::Handle or FileHandle, give the formats different names, and say STDOUT->format_name("whatever"); before the write (whatever will be qualified with the current package.)	[reply]