Of course I don't mind questions, on the contrary, I'm interested to answer as much as I can, otherwise it won't be clear to me what parts of docs are insufficiently explained. So fire away!

With sleep, and all the predicates, I see where confusion stems from. All of the predicates accepts parameters on two stacks. The callback itself is the only parameter that is passed using perl stack, and all predicates have (&) signature for exactly that. All the other parameters are passed in the context.

Back to your question, a signature of sleep. The doc says that it is "sleep($deadline)", and is correct in that regard, because it omits two facts that all predicates a) have perl signature (&) and b) always deal with callbacks, so callbacks were not mentioned too.

Thus, passing the call as &sleep($deadline) is not correct, but &sleep($_[0]) is. sleep(&) expects the callback in $_[0], and deadline in context[0]. Hope that dissolves the confusion.

Finally, predicates. It seems that the word has many notions, and can be confusing. I'll need to document that term much more thoroughly, - or even consider another name?

In reply to Re^8: IO::Lambda: call for participation by dk
in thread IO::Lambda: call for participation by dk

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


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.