Logos Improvements

[DHowett]

• %log() => static function (what?)
• %init => static function (is this maybe what I meant?) (%init should just call a static function generated at the end #19)
• %config(logs=...) (%config(logs=...) #16)
• ivar get/set/creation (for %subclass)
• log applied hooks
• control %log output
• category generation for %new methods
• %append/%prepend (=> %flag?) a la http://ghostbin.com/paste/mycpg
  • return value passing a la http://ghostbin.com/paste/tvyvy
• dealloc warnings
  • dealloc should be prepend, if the concept flies
• unique noncustom classes across groups
• refactor %c into generic cached computation functionality (Refactor %c into generic cached computation functionality #15)

[DHowett]

I have no idea what I was doing with this (%log => static function? what?), and that makes me sad. Repurposing as logos improvement bug.

[theiostream]

What is the use case of %append/%prepend?

Also, just figure I'll put it here, find cool %ivar syntax.

[caughtinflux]

Replace __PRETTY_FUNCTION__ with the corresponding hooked method name, to keep all the $$$ safe, not to mention clarity.

[DHowett]

%group X %init Y %end %end might create _logos_class$_ungrouped$Y.

[caughtinflux]

For the ivar syntax, would it be possible to simply declare them after a %subclass directive? Like so

%subclass Foo : Bar 
{
    id _fooBar;
}
...
%end

Are there any limitations that prevent Logos from doing this, keeping all the leg work behind the scenes (like everything else it does ;P)?

[DHowett]

Main issue there is that I don't actually parse source. Syntel has a type parser, and it's possible at the very least to get into subclass blocks for ivars (ooh: treat them like syntelstructs! good idea!), but that would ideally be coupled with direct reference to ivar names. And that is dark magic indeed.

[DHowett]

Looked into __PRETTY_FUNCTION__; it's handled as a primary-expression in the C parser. We can unfortunately not get inside it :(

[DHowett]

From #48.

17:22 <@DHowett> that should be being done anyway, come to think of 
             it. however, it complicates custom class expressions
17:22 <@DHowett> as init can wrap scope
17:22 <@DHowett> (the function cannot be variadic, and i do not know 
             what classes the user will want to change
17:22 <@DHowett> actually, that's tractable. i think it can be done)
17:23 <@DHowett> (the static function gets generated at the end, after 
             all. the call can contain all overridden classes)
17:23 <@DHowett> and the prototype and final function as well

[DHowett]

From #10.

The logs config param for logos should exist, and support full, off, and on (defaulting to on). full will automatically %log all hooked methods. off will disable (consume) %log directives.

[DHowett]

From #9 (via @rpetrich).

It should be possible to pass arbitrary expressions into a logos macro and have it dedupe and cache them.
Existing %c(classname) expressions could be converted to use this functionality internally.
Additionally, components within theos itself could use this functionality to trim some of the work they perform (would use this for my internal generator)

Proposed syntax:
%cached(x) yields a C rvalue that references the result of the computation x as executed from inside %init; (or the automatically generated initializer if none exists)

Potential extensions:
Nested cached expressions could be supported to eliminate duplicate work inside of cached expressions themselves. Further, cached expressions that are used only as a subexpression of other cached expressions could be optimized not to escape the scope of %init
Lazy initialization via alternate syntax (with/without thread safety?). Would allow syntax like this to workaround glacial apis:
%cached([[[NSCharacterSet characterSetWithCharactersInString:@"_1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"] invertedSet] retain], lazy)

[nathggns]

Someone implemented %property in a pull request - #94