Re: [e4-dev] Dynamic Eclipse 4 with Clojure language

[Laurent PETIT <laurent.petit@xxxxxxxxx>]

2013/11/25 Tom Schindl <tom.schindl@xxxxxxxxxxxxxxx>:
> On 23.11.13 00:32, Laurent PETIT wrote:
>> Clojure & Eclipse 4 Update status:
>>
>> = TL;DR
>> - "org.eclipse.e4.languages" extension point is *the way* to glue
>> Clojure and the E4 Model together.
>> - Having DI / Behavioral Annotations work from Clojure-only without
>> any java class involved will require some more work from my part
>> (generating bytecode via ASM).
>>
>> = Detail
>>
>> == Annotations
>> E4 Annotations and Clojure Types don't work well together. Anyway,
>> Clojure Types weren't really made for this usecase, so:
>> - as a first step I just created stub java classes with annotations.
>> - in a second step I intend to generate annotated classes dynamically
>> via the ASM (bytecode generation / manipulation) library.
>>
>> == Contributions via contributionURI
>> Tom made me look closely at how ReflectionContributionFactory works.
>> And it includes a working hook to provide my own
>> IContributionFactorySpi, via the "org.eclipse.languages" extension
>> point, like this:
>>
>>    <extension point="org.eclipse.e4.languages">
>>       <language
>>             contributionFactory="ccw.util.ClojureContributionFactorySpi"
>>             name="clojure">
>>       </language>
>>    </extension>
>>
>
> As you can see the SPI allows to call methods as well. So I ask myself
> if we could tunnel method calls through the SPI as well, hence no need
> have annotations.
>
> Looking at the call method i'm not sure although if we don't need a
> different signature.

I have indeed not taken the second method of the SPI into account.
Just throwing a NotSupported exception at the moment.
A quick seach for callers returned nothing for this method as well.

So I haven't thought about possible usages of this method call. For a
language like Clojure which uses concepts of functions preferably to
objects with methods, I'm not sure it will help a lot if the semantics
are "calling a method of an object" (as opposed, for instance, as
"leveraging some feature - such as @Execute-ing for some object")
=> So indeed, the answer for my usecase could depend on what exact
information the signature of this method conveys.

>
>> This is perfect, it allows me to write contributionURIs like
>> contributionURI="bundleclass://ccw.core/clojure/some.namespace/some-var"
>>
>> This will allow me to totally leverage the Eclipse 4 Model from
>> Clojure, without compromises!
>>
>> Please, please, don't tell me you intend to deprecate / remove
>> org.eclipse.e4.languages, it's a fantastic hook for alternate
>> languages on the JVM !
>
> To my knowledge you are the only one using this and it's NOT official
> API yet

Not sure I'm the only one to use it: I have seen mentions of usages of
the org.eclipse.e4.languages extension point here:
http://wiki.eclipse.org/E4/JavaScript, as returned by Google with a
search on ( "org.eclipse.e4.languages" javascript )