I am working on a project where I have to read list of
environment variables from configuration file and
execute perl “eval” to expand the environment variable
and write it to new file.
I have a condition,
(defined $ENV{HOST} ? $ENV{HOST} : 'SQLHOST')
if HOST is not defined garb a string.
So I tried following making environment variable HOST undefined which work, 
my $val;
my $stmt = q{$val = (defined $ENV{HOST} ? $ENV{HOST} : 'sqlhost')};

eval $stmt;

if ($@)
{
    print $@, "\n";
    }
    else
    {
        print $val, "\n";
    }

[download]
OUTPUT= "sqlhost"

But I am suppose to read the configuration file so I tried this, 
my ($r, $stmt);

while ($stmt = <DATA>)
{
    eval $stmt;

    print "$stmt\n";

    if ($@)
    {
        print $@, "\n";
    }
    else
    {
        print $r, "\n";
    }
}

__DATA__
$r = (defined $ENV{HOST} ? $ENV{HOST} : 'sqlhost')

[download]
OUTPUT= "$r = (defined $ENV{HOST} ? $ENV{HOST} : 'sqlhost')"

it didn;t work can any one suggest me better solution?
Thanks

In reply to eval, Read environment variable and expand using eval by tart

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