[Twisted-Python] Multiple plugins in "twistd"

[Glyph]

> On May 19, 2015, at 14:01, Tom Prince <tom.prince at ualberta.net> wrote:
> 
> Glyph <glyph at twistedmatrix.com> writes:
> 
>> You could also find some other way to split the argument list but "+" doesn't seem particularly obscure in this context to me.  (If there's really a need to pass a literal "+" to a plugin we could add an escaping syntax as well.)
> 
> I think if we are adding syntax, then we should also add escaping at the
> same time.
> 
> On a related note, when designing this kind of syntax, I think it is
> often valuable to explictly leave some of the space as an explict error,
> to leave freedom to extend the syntax in the future.
> 
> I wonder if there is any value in having a syntax that is nestable. I
> don't see any specific use case, but I can imagine wanting ot pass
> options to `compose` that are scoped to an individual plugin that it is
> loading. And then, maybe you want to nest things so that those options
> apply to a subset of plugins, which might naturally be implemented as
> compos of a compose.
> 
> The suggestions in the last paragraph are perhaps somewhat contrived,
> and certainly not something that should be *implemnted* in a first (or
> even second pass). But considering the possiblity, and then picking a
> syntax that might allow those kinds of extension (and then explictly
> making the extension syntax an error) gives us the ability to add those
> features without breaking backwards compatibility.

We can un-escape '\+' as a token just fine, and if we do that, all of the weird use-cases you just described are possible.  I can't think of any options I'd want to pass to 'compose' myself, but it would be easy enough to add some flags to its parser.

-g