RE: [drew.adams@oracle.com:RE:weirddefadvicebugwithbyte-compilation]

["Drew Adams" <drew.adams@oracle.com>]

Sorry - sending again as plain text. My mail client sends formatted text
whenever I reply to a Unicode message.

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        > And I wonder about the behavior of the on-the-fly defadvice
        > byte-compiling. Again, I'm no doubt confused about that - I'd like
        > to understand what's happening there and why.

        See `ad-default-compilation-action'.

    Thanks very much. I never heard of that variable. Or, I may
    have read about it, but never paid adequate attention. Here is
    its doc string:

      Defines whether to compile advised definitions during activation.
      A value of `always' will result in unconditional compilation,
      `never' will always avoid compilation, `maybe' will compile if the
      byte-compiler is already loaded, and `like-original' will compile
      if the original definition of the advised function is compiled or
      a built-in function.  Every other value will be interpreted as
      `maybe'.  This variable will only be considered if the
      COMPILE argument of `ad-activate' was supplied as nil.

    The default value is `maybe', and that's the value I had. The
    doc string says that that means that activation will also
    compile - if the byte-compiler is already loaded. I have no
    idea what loads the byte compiler, or why its being loaded
    would be the criterion applied here, but I must assume that in
    my case it was already loaded, and that that is the default
    situation (?). How to tell if it is loaded?

    The doc string also says that this only happens if the COMPILE
    arg to ad-activate is nil. Well, I never explicitly called
    ad-activate, with or without a COMPILE arg - I used only
    defadvice. But I guess the `compile' FLAG for defadvice acts
    like the COMPILE arg to ad-activate in this regard (not
    mentioned in the doc string). Is that correct?

    Does this all seem a bit convoluted to anyone besides me? Does
    anyone else think that, at the very least, the doc string of
    defadvice should clarify that the meaning of not using the
    `compile' flag can be overridden by the value of
    `ad-default-compilation-action' - depending on that variable's
    value, and that it will be overridden by the default value
    (`maybe') in the default configuration (byte-compiler loaded)?

    What goes for the doc string of defadvice also goes for the
    description in Info (Elisp).

    Apparently, the already elaborate description of defadvice in
    Info (node "Defining Advice") is far from being enough for
    someone to understand how to use defadvice in even a simple case.