in reply to Re^2: An Unreal Perl Hacker!
in thread An Unreal Perl Hacker!

Thanks, I am more enlightened :0). But I cannot imagine the typical (and ideal) case of use. Can you, please, describe user's goal, user's input, what happens in the guts, and output?

Replies are listed 'Best First'.
Re^4: An Unreal Perl Hacker!
by samizdat (Vicar) on Oct 14, 2005 at 13:08 UTC
    Sure. Suppose noob comes up to his screen with a program that isn't working right: 
    #!/usr/bin/perl

for ($i=0,$i<=5,$i++)
{ 
    print "FOO\n"; 
}

    [download]
    which prints: 
    FOO
FOO
FOO

    [download]
    no matter what he does. (classic newbie mistake that used to bug me when I was doing C :) He checks a box that says "output is incorrect."

    Our critter will extract the for() loop from his code, and wrap it in : 
    eval 
{
  for (i=0,$i<=5,$i++)
  { 
      print "FOO\n"; 
  }
};
print "'$@'";

    [download]
    This tells our critter that the code did execute. It's next step is to examine node replies for similar code fragments. Pretty soon (!), it discovers that a for() loop should have ';' instead of ',' as iterator separators, and hands back the code: 
    #!/usr/bin/perl
for ($i=0;$i<=5;$i++)
{ 
    print "FOO\n"; 
}

    [download]
    A further refinement would have it make a scope declaration pass, and hand back: 
    #!/usr/bin/perl
use strict;
use warnings;
for (my $i=0;$i<=5;$i++)
{ 
    print "FOO\n"; 
}

    [download]
[reply]
[d/l]
[select]
      Thanks for reply, good idea, I keep it in mind for my week-end contemplations :) Specially, how much complicated code could be (succesively) processed by this way, and, if this can be effective with a small set of categorized context (
      my $current_context = ['syntax error','unexpected warning','unexpected
+ output','neverending loop'];

      [download]
      )
[reply]
[d/l]
        I think the goal here should be to figure out something that can help in some cases, and then expand the scope of {some}.
[reply]

In Section Perl Monks Discussion