Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl Monk, Perl Meditation
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??
I cant come up with a good example right now, but there are definitely times where i'd want false (but defined) to indicate a behavior different than for undef.

Likely, shemp was thinking along the lines of an optional numeric option. A crazy example I can think, goes along the lines of "how many errors will this parser tolerate before throwing an exception".

You could leave the option undef to mean "no amount of errors will make me throw an exception", zero (also false) to mean "allow no errors at all" and a positive value (true) to mean "allow for up to this many errors".

However, the most common usage is to have undef stand for "not specified/wanted" and a true value for the contrary.

Best regards

-lem, but some call me fokat


In reply to Re^2: Getopt::Long to define or not to define? by fokat
in thread Getopt::Long to define or not to define? by jordanh

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others learning in the Monastery: (5)
As of 2024-03-28 14:17 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found