Question

I want to do the same thing as

open MYFILE, ">", "data.txt";
print MYFILE "Bob\n";

but instead in class variable like

sub _init_tmp_db
{
    my ($self) = @_;

    open $$self{tmp_db_fh}, ">", "data.txt";
    print $$self{tmp_db_fh} "Bob\n";
}

It gave me this error : ‘String found where operator expected near “Bob\n”‘

what should I do?

Answer 1

From the print manpage:

If you’re storing handles in an array or hash, or in general whenever
you’re using any expression more complex than a bareword handle or a
plain, unsubscripted scalar variable to retrieve it, you will have to
use a block returning the filehandle value instead.

You should be using:

print { $$self{tmp_db_fh} } "Bob\n";

This code won’t work under use strict. To fix it just use a my variable:

open my $fh, ">", "data.txt" or die $!;
$$self{tmp_db_fh} = $fh;
print { $$self{tmp_db_fh} } "Bob\n";