devxlogo

A Quick-and-dirty Script for “Direct Mode” in Perl

A Quick-and-dirty Script for “Direct Mode” in Perl

Ever get annoyed that there’s no “direct mode” environment in Perl? Instead, you have to save your code to a file and then execute it everytime. To offset this, I wrote this small program allows me to type and execute Perl code, complete statement by statement.

Here’s how to use it. Save the code to a file named ‘direct.pl’, and start it. When the “>” prompt shows, type (or copy & paste from notepad) your code. When you press enter, it will execute it, show the result, and wait for next line. This script is quick-and-dirty?meaning it’s not perfect and may not work every time but hey, that’s not the point. It will try to count and show the number of open brackets/braces/parenthesis for you, and will execute the statement only when you close them.

my $count = 0;my $statement = "";print "
> ";while (<>) {  chomp;  s/([^$\])#.*$/$1/;  while (/{|(|[/g) {$count++};  while (/}|)|]/g) {$count--};  $statement .= $_;  if (!$count) {    $_ = eval $statement;    print "
[$_]
";    if ($@) {print "Error: $@
"};    $statement = " ";    print "> ";  }  else {    print "$count> ";  }}
See also  Professionalism Starts in Your Inbox: Keys to Presenting Your Best Self in Email
devxblackblue

About Our Editorial Process

At DevX, we’re dedicated to tech entrepreneurship. Our team closely follows industry shifts, new products, AI breakthroughs, technology trends, and funding announcements. Articles undergo thorough editing to ensure accuracy and clarity, reflecting DevX’s style and supporting entrepreneurs in the tech sphere.

See our full editorial policy.

About Our Journalist