Hour 12. Using Perl s Command-Line Tools

Hour 12. Using Perl's Command-Line Tools

What You'll Learn in This Hour:

• How to use Perl's debugger

• How to use command-line switches to write small Perl programs

Until now, the Perl interpreter has been a fairly simple program to use. You type a program into a file and then invoke the Perl interpreter to run your program. The Perl interpreter is much more flexible than this, however.

Built into the interpreter is a debugger. The debugger allows you to play your Perl program like a videotape. You can rewind your program to the beginning, play it slow, play it fast, and freeze-frame it to examine the innards closely. The debugger is an often underutilized tool for finding problems in Perl programs.

Perl can also run programs that are not typed into files. For example, you can run small programs directly from your system's command prompt.