1171: Perl Problems

2013-02-10T04:54:38Z

Brightonsimon:

{{comic
| number = 1171
| date = February 8, 2013
| title = Perl Problems
| image = perl problems.png
| titletext = To generate #1 albums, 'jay --help' recommends the -z flag.
}}

==Explanation==
{{w|Perl}} is a scripting language that makes heavy use of {{w|Regular expression|regular expressions}}, which are good for dealing with large amounts of text quickly. In the comic, the man wearing sunglasses parodies the song "{{w|99 Problems}}" in which the rapper {{w|Jay-Z}} says:

:If you're havin' girl problems
:I feel bad for you, son-
:I got 99 problems,
:But a bitch ain't one.

In the comic however, the rapper tries to solve his problems with Perl’s regular expressions, and ends up only creating another problem for himself, which is a reference to a [http://regex.info/blog/2006-09-15/247 famous quote by Jamie Zawinski] (whose name could also be shortened to "Jay-Z"): “Some people, when confronted with a problem, think ‘I know, I'll use regular expressions.’ Now they have two problems.”

In perl (and php), using a command like preg_match(exp,str) will generate an extra match: the first match contains the entire string, while the remaining will contain every instance in which it matched.

Novice users are often surprised when they perform a preg_match and set the values to an array, like

$matches = preg_match('/[A-Za-z]/i',$str);

and then try to use the first result in that array, like:

$firstMatch = $matches[0];

...only to get the whole original string back, leaving them where they started.

“program --help” is a common way, originating with the GNU project, to ask a program to show documentation on its usage and supported parameters; which, for some program, could include a “-z” command-line argument (“flag”), so the command would read "jay -z". In this case, it is just an obvious play on the rapper’s name. [http://www.cs.rit.edu/~ats/projects/lp/doc/jay/package-summary.html '''jay'''] is also an actual C program that is a compiler-compiler for java.

==Transcript==
:[Man with sunglasses and Cueball talking.]
:Sunglasses: If you're havin' perl problems I feel bad for you, son-

:Sunglasses: I got 99 problems,

:Sunglasses: So I used regular expressions.

:Sunglasses: Now I have 100 problems.

{{comic discussion}}
[[Category:Perl]]
[[Category:Music]]
[[Category:Comics featuring Cueball]]

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1171: Perl Problems