No, I guess so. So it sounds like you're saying I should forget it and move on to the next thing? I.e. it's not feasible to get at this in a static analysis context?
On Tue, Sep 22, 2015 at 10:24 AM, Cédric Champeau <cedric.champ...@gmail.com > wrote: > Just for context and history, early versions of the type checker had > return type inference for methods too. However, we removed it for a good > reason: overrides. A method "foo" in class A can have an inferred type T, > but "foo" from B extends A could very well have a different inferred type > T2. So you can make no guarantee, at least for non private methods. > > > 2015-09-22 11:19 GMT+02:00 Jamie Echlin <jamie.ech...@gmail.com>: > >> Hi Shil, >> >> I did that actually, but it tells me the return type of the run method of >> Script is Object. Which is expected, if it's just looking at the actual >> method signature. >> >> But what I was hoping for is that given a script: >> "new Double(2)" >> >> it would be able to infer the actual return type is a Double. Now, I can >> imagine scripts where you randomly pick from any class on the classpath, >> invoke a no-args constructor, and return that... in that case I don't >> expect magic. But most scripts have one or two possible return statements >> (maybe implicit), I'm wondering if there is already code that can >> statically analyse a method/script and say that there are only one, two or >> whatever possible return types. >> >> I'll take a look at ReturnAdder, thanks for that. >> >> cheers, jamie >> >> >> On Mon, Sep 21, 2015 at 11:55 PM, Shil Sinha <shil.si...@gmail.com> >> wrote: >> >>> Actually, the second option can be made safe by initializing ReturnAdder >>> with a listener, which will allow you to 'visit' all implicit returns >>> without actually adding return statements. >>> >>> On Mon, Sep 21, 2015 at 5:30 PM, Shil Sinha <shil.si...@gmail.com> >>> wrote: >>> >>>> You could call 'getInferredReturnType' on the 'run' method node of your >>>> script class, but inferred return types only appear to be stored for >>>> closures and certain binary expressions (based on the usages of the >>>> INFERRED_RETURN_TYPE marker and the storeInferredReturnType method). >>>> >>>> You could also add all implicit return statements to the 'run' method >>>> via ReturnAdder, and then infer a return type by visiting all of the return >>>> statements, but I'm not sure if that kind of AST modification in a type >>>> checking extension is safe. >>>> >>>> Shil >>>> >>>> On Mon, Sep 21, 2015 at 4:34 PM, Jamie Echlin <jamie.ech...@gmail.com> >>>> wrote: >>>> >>>>> Hi... >>>>> >>>>> Is it possible to infer the return type, or types of a script during >>>>> static compilation? Presumably there is always a finite list of branches >>>>> where the script could end. >>>>> >>>>> I'm looking >>>>> at >>>>> org.codehaus.groovy.transform.stc.StaticTypeCheckingVisitor#getInferredReturnType, >>>>> but I'm not really sure how to call it from a type checking script, nor >>>>> what adds the inferred return type to the metadata which is used in that >>>>> method. >>>>> >>>>> cheers, jamie >>>>> >>>> >>>> >>> >> >
