Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl: the Markov chain saw

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

I should have mentioned in my original post that there is another set of special cases for this purpose. Perl silently ignores leading and trailing whitespace when numifying a string (which AFAIK is not widely known nor documented, although a pointer to the relevant docs are welcome). So there are an infinite set of strings which are false numerically, but true in boolean context. (And an infinite set of strings which are numerically equivalent to any integer you choose.)

perl -wle'my $n= (" " x 1_000_000) . "0" . (" " x 1_000_000); print $n + ? "true" : "false", " as a bool, prenumification"; print 0+$n ? "tru +e" : "false", " as a bool, numified"; print $n ? "true" : "false", " +as a bool, postnumification";' true as a bool, prenumification false as a bool, numified true as a bool, postnumification

This is not generally a problem except for people who write serializers and need to ensure that " 0 " round trips correctly.


In reply to Re^7: The True but Zero value? by demerphq
in thread The True but Zero value? by Marshall

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 or How to display code and escape characters are good places to start.
Log In?

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

How do I use this? | Other CB clients
Other Users?
Others pondering the Monastery: (5)
As of 2022-05-23 08:11 GMT
Find Nodes?
    Voting Booth?
    Do you prefer to work remotely?

    Results (81 votes). Check out past polls.