Hi,

I'm using someone else's code which opens a file for reading like so: 

$fh = do {local *FH};
open ($fh, $filename)

[download]
I'd never seen that trick before. I found an explanation here: http://perl.plover.com/local.html#3_The_First_Class_Filehandle_Tr.

I want to be able to report the last line number read. I could use $., but I thought IO::Handle's input_line_number method would be better (so I don't have to worry about whether this filehandle was the last one accessed).

However, IO::Handle seems not to like the "do {local *FH};" trick. Here's a small example:

use strict;
use warnings;

use IO::Handle;
my $fh;
# $fh = do {local *FH};   #bad
open ($fh, './test') or die("open failed: $!");
print "line: " . $fh->input_line_number();

__END__

output with "#bad" commented out:
line: 0

output with "#bad" included:
Can't call method "input_line_number" without a package or object refe
+rence at test line 10.

[download]
I have two easy workarounds -- use $. carefully, or modify the original code -- but I was wondering if there's a cleaner way of getting the line number?

Thanks,
Joe

In reply to Last Line Read? (Any way to use IO::Handle methods on a "First-Class" Filehandle?) by blahblahblah

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