Re: minor problem in summary

On Sat, Sep 11, 2004 at 03:29:23PM -0600, Andrew Dalke wrote:
> I was reading through
> 
>   Sample solutions and discussion
>   Perl Quiz of The Week #23 (20040901)
> 
> and saw
> 
> """
> The results for the Perl code are:
>   ...
>   dalke.py                B N L U
>   ...
> The results for the non-Perl code are:
> 
>   dalke.py                skip
> """
> 
> How did that come about?  Since there are timings for my
> program, I'll assume that it did run,  and I know it
> wasn't in Perl.  :)
> 

Wow, tracking down exactly what happened here has been a learning
experience for me.

At first, I couldn't get it to run, probably because I was running it
without any command-line options.  The error message is:

    File "dalke.py", line 10
      yield ")" * open_count
              ^
  SyntaxError: invalid syntax

I think I saw this once and gave up on your solution.  This may have
been just after I installed a Haskell compiler.  :^)  So where did the
BNLU and the timing data come from?

The answer: at one point I was working with a file named 'unskipped',
listing the scripts I was able to run.  I neglected to remove dalke.py
from this file.  This tidbit (new to me) from perlrun tells the rest:

  If the #! line does not contain the word "perl", the program named
  after the #! is executed instead of the Perl interpreter.  This is
  slightly bizarre, but it helps people on machines that don't do #!,
  because they can tell a program that their SHELL is /usr/bin/perl, and
  Perl will then dispatch the program to the correct interpreter for
  them.

So my testing script invoked dalke.py with /usr/bin/perl, and perl knew
to use the python interpreter to run your script.  Amazing!