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XtendParser [message #540542]

Wed, 16 June 2010 09:25

Eclipse User

There could be a larger oAW community here

Anyone knows how we can get an AST by parsing an .ext file by using XtendFacade? I can only see that we could get an ExtensionFile object. I have tried to parse an .ext file to get an ExtensionFile object but not successful yet

ExtensionFile f = ParseFacade.file(new StringReader(expression), fileName);

expression is a string but I don't understand what should I assign for it

Please help!

Re: XtendParser [message #540559 is a reply to message #540542]

Wed, 16 June 2010 10:17

Eclipse User

Use the XtendFacade, passing the path to the .ext file relative to the classpath.

If you have the ExtensionFile instance that's actually the AST.

You should consider looking into the Xtend test plugin for some sources.
CVS coordinates:
- dev.eclipse.org
- /cvsroot/modeling
- org.eclipse.m2t/org.eclipse.xpand/plugins/org.eclipse.xtend. tests

~Karsten

Re: XtendParser [message #540653 is a reply to message #540559]

Wed, 16 June 2010 16:36

Eclipse User

Thank you so much!

I have looked into org.eclipse.m2t/org.eclipse.xpand/plugins/org.eclipse.xtend. tests and there are many examples there

I tried one of them but now I have another problem with java.lang.NullPointerException at this point:
ec = (ExecutionContextImpl) ec.cloneWithResource(file);

I am quite sure that parse function works well because I can read some information from the instance of ExtensionFile. Thus I don't understand why NullPointerException is there Confused

Here is the test code:
ec = new ExecutionContextImpl();
ec.registerMetaModel(new JavaMetaModel("JavaMetaModel", new JavaBeansStrategy()));

final ExtensionFile file = parse(
"foo(String str) : 'String';" +
"foo(Integer int) : 'Int';" +
"foo(Void void) : 'void';");
ec = (ExecutionContextImpl) ec.cloneWithResource(file);
XtendFacade facade = XtendFacade.create(ec);
assertEquals("String",facade.call("foo", "String"));
assertEquals("Int",facade.call("foo", new Long(42)));
assertEquals("void",facade.call("foo", (Object) null));

Re: XtendParser [message #540727 is a reply to message #540542]

Thu, 17 June 2010 04:06

Eclipse User

sorry, my fault!
This code works well Smile

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