Eclipse Community Forums: TMF (Xtext) » Type Inference with XBase

Help

Home

Home » Modeling » TMF (Xtext) » Type Inference with XBase

Show: Today's Messages :: Show Polls :: Message Navigator

Type Inference with XBase [message #769512]

Thu, 22 December 2011 08:12

peter

Messages: 5
Registered: December 2011

Junior Member

Hy,
In my Xbase dsl I need to define some operations with no return type explicitly declared. I also need to use the inferer to map my concepts with Java.
I'm wondering which would be the best practice to determine an implicit XExpession return type so that it could be infered with Java.
I'm currently experimenting this on the domainmodel. On it's dsl I removed the "operation" rule return type:

Operation:
'op' name=ValidID '(' (params+=FullJvmFormalParameter (',' params+=FullJvmFormalParameter)*)? ')' '=' //initially there was ':' type=JvmTypeReference
body=XExpression; //initially there was body = XBlockEx..

The new operation return type should normally be the XExpression return type.
On DomainmodelJvmModelIferrer I injected an ITypeProvider and I changed the Operation code like this:

Operation : {
members += f.toMethod(f.name, f.body.type) [ //I request here the XExpression return type
documentation = f.documentation
for (p : f.params) {
parameters += p.toParameter("p", p.parameterType)
}
body = f.body
]
}

The problem is that f.body.type always returns "null" and consequently the infered return type of java operation is always void.

A model exemple, just in case:

package dmodel{

entity Person{
name: String
age: Integer

op getName0() = age //Integer

op getAge0() = age //String

op getAge1() = getAge0() //This should normally be a String
}

What should I consider in order to make this working?
This is quite similar with Xbase/Xtend type inference and i'm sure that it could be done somehow.
Thanks!

Report message to a moderator

Re: Type Inference with XBase [message #769577 is a reply to message #769512]

Thu, 22 December 2011 11:05

Jan Koehnlein

Messages: 760
Registered: July 2009
Location: Hamburg

Senior Member

You should not resolve any cross references during JVM model inferrence.
To make this work in Xtend, we have implemented a special type proxy.

org.eclipse.xtext.xtend2.jvmmodel.Xtend2JvmModelInferrer.getTypeProxy(EObject)

Should give you an entry. I have a feeling this needs more documentation...

Am 22.12.11 09:12, schrieb peter:
> Hy,
> In my Xbase dsl I need to define some operations with no return type
> explicitly declared. I also need to use the inferer to map my concepts
> with Java.
> I'm wondering which would be the best practice to determine an implicit
> XExpession return type so that it could be infered with Java.
> I'm currently experimenting this on the domainmodel. On it's dsl I
> removed the "operation" rule return type:
>
> Operation:
> 'op' name=ValidID '(' (params+=FullJvmFormalParameter (','
> params+=FullJvmFormalParameter)*)? ')' '=' //initially there was ':'
> type=JvmTypeReference
> body=XExpression; //initially there was body = XBlockEx..
>
>
> The new operation return type should normally be the XExpression return
> type.
> On DomainmodelJvmModelIferrer I injected an ITypeProvider and I changed
> the Operation code like this:
>
> Operation : {
> members += f.toMethod(f.name, f.body.type) [ //I request here the
> XExpression return type
> documentation = f.documentation
> for (p : f.params) {
> parameters += p.toParameter("p", p.parameterType)
> }
> body = f.body
> ]
> }
>
> The problem is that f.body.type always returns "null" and consequently
> the infered return type of java operation is always void.
> A model exemple, just in case:
>
> package dmodel{
>
> entity Person{
> name: String
> age: Integer
>
>
> op getName0() = age //Integer
>
> op getAge0() = age //String
>
> op getAge1() = getAge0() //This should normally be a String
> }
>
> What should I consider in order to make this working?
> This is quite similar with Xbase/Xtend type inference and i'm sure that
> it could be done somehow. Thanks!
>
>
>
>
>

--
Need professional support for Eclipse Modeling?
Go visit: http://xtext.itemis.com

---
Get professional support from the Xtext committers at www.typefox.io

Report message to a moderator

Re: Type Inference with XBase [message #769584 is a reply to message #769577]

Thu, 22 December 2011 11:17

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

Hello Jan,

this wont work neither cause org.eclipse.xtext.xbase.jvmmodel.JvmTypesBuilder.cloneWithProxies(JvmTypeReference)
doesnt like proxies so one might have to do some extra stuff.

~Christian

Twitter : @chrdietrich
Blog : https://www.dietrich-it.de

Report message to a moderator

Re: Type Inference with XBase [message #769604 is a reply to message #769584]

Thu, 22 December 2011 12:02

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

Just gave it a deeper try and it actually works

(using a own DomainModelResource, a customized JvmTypesBuilder and some extra work to the Inferrer)

~Christian

Twitter : @chrdietrich
Blog : https://www.dietrich-it.de

Report message to a moderator