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Re: UFO (Unidentified Formatting Observation) on the web....

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Jeff 'japhy' Pinyan
February 1, 2002 07:49
Re: UFO (Unidentified Formatting Observation) on the web....
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On Feb 1, Ron Goral said:

>I have a very beginner's question.  I've just been looking at the code for a
>library file and noticed some, to me, very peculiar things.  First, there is
>text that is not commented, it is just typed in place.  Why does this not
>interfere with the script?  Second, there are expressions like "=pod" and
>"=cut" and "=head1".  What do these mean?  Third, there is a "1;" at the
>very end of the file.  I've seen that before, but what is the purpose?
>Fourth, there is text like "I<delete_cookie> blah blah" and "B<MUST>" (I
>assume that this last is a comment on text decoration).  Can anyone tell me
>what these mean?  Is there a difference in a library file and a regular
>script file that allows for this?   Is there some tutorial or documentation
>about the differences in writing a library/module versus a normal script

The text that "is not commented", you will find, is placed inbetween the
=XYZ statements.  The =XYZ statements are called Pod directives, and the
I<...> and B<...> statements are Pod markup.  Pod is "Plain Old
Documentation", a very simple markup language for documenting Perl

Read 'perldoc perlpod' for information on Pod.

The '1;' at the end of the file is there so that the file returns a true
value when Perl require()s it.  See 'perldoc -f require'.

As for how a library or module differs from a "normal" program, it's
basically how an encyclopedia differs from your term paper.  You READ your
term paper, and it makes references to places in the encyclopedia -- you
wouldn't use the entire encyclopedia as your term paper.

Jeff "japhy" Pinyan
RPI Acacia brother #734
** Look for "Regular Expressions in Perl" published by Manning, in 2002 **
<stu> what does y/// stand for?  <tenderpuss> why, yansliterate of course.

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