Beefy Boxes and Bandwidth Generously Provided by pair Networks
Do you know where your variables are?
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??

Thank you all for useful links and answers, I should have done better research to at least find ref to read-only alias ... why?, which itself links far further into the past. Still not sure how to justify why with foo(1+1) the $_[0] is OK to be writeable, but with foo(1) it should die. Following previous discussion, the impression now is that it's either not a bug but vague (because of dynamic language(?)) area, or bug of very low priority, fixing of which can break/slower existing code (?).

As to from where I started (foo(pack 'P', $data)), with hindsight, of course $_[0] is "pointable" for as long as staying within a sub, and returning that pointer to outside is entirely programmer's (my) fault, Perl couldn't help :(


In reply to Re^2: When aliasing sub arguments to @_ elements, PADTMP, READONLY flags are copied inconsistently by vr
in thread When aliasing sub arguments to @_ elements, PADTMP, READONLY flags are copied inconsistently by vr

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 wandering the Monastery: (7)
As of 2024-04-23 14:28 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found