Programming PERL in the .NET Environment

Special Perl Variables

As you learn Perl, you will become familiar with many special Perl variables, each of which arms the Perl programmer with a more elegant way of writing some code. Probably the most common special variable is named $_. This variable plays a few important roles in the life of a Perl programmer.

The Default Input and Output Variable $_

Earlier, we presented a segment of code that read lines from the standard input and printed them.

while($line = <STDIN>)
{
    print $line;
}

Within a loop, if you do not name a variable to be the recipient of the input, Perl uses the variable $_ by default. Likewise, if you do not give any arguments to the print function, then $_ is printed by default. Thus, the above code could have been written ...