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Submitted by Neil in a forum post:

Walking the AST throws an error when it encounters a user-defined function that returns a CLASS:

    FUNCTION newAppError RETURNS /*CLASS*/ Progress.Lang.AppError PRIVATE
        (INPUT ipcMessage AS CHARACTER) FORWARD.

results in the following errors thrown during the AST walk, which results in termination of the analysis at that point:

        [java] EXPRESSION EXECUTION ERROR:
     [java] ---------------------------
     [java] throwException(errmsg)
     [java] ^  { Unrecognized return type FUNC_CLASS [KW_FUNCT id <1451698947492> 356:1] }
     [java] ---------------------------
     [java] EXPRESSION EXECUTION ERROR:
     [java] ---------------------------
     [java] cls = execLib("get_function_return_class", ftype)
     [java]       ^  { Expression execution error @1:1 }
     [java] ---------------------------
     [java] ERROR:
     [java] com.goldencode.p2j.pattern.TreeWalkException: ERROR!  Active Rule:
     [java] -----------------------
     [java]       RULE REPORT      
     [java] -----------------------
     [java] Rule Type :   WALK
     [java] Source AST:  [ FUNCTION ] BLOCK/FUNCTION/KW_FUNCT/ @356:1 {1451698947492}
     [java] Copy AST  :  [ FUNCTION ] BLOCK/FUNCTION/KW_FUNCT/ @356:1 {1451698947492}
     [java] Condition :  throwException(errmsg)
     [java] Loop      :  false
     [java] --- END RULE REPORT ---
     [java] 
     [java] 
     [java] 
     [java]     at com.goldencode.p2j.pattern.PatternEngine.run(PatternEngine.java:1068)
     [java]     at com.goldencode.p2j.convert.ConversionDriver.processTrees(ConversionDriver.java:1128)
     [java]     at com.goldencode.p2j.convert.ConversionDriver.front(ConversionDriver.java:382)
     [java]     at com.goldencode.p2j.convert.ConversionDriver.main(ConversionDriver.java:2005)
     [java] Caused by: com.goldencode.expr.ExpressionException: Expression execution error @1:7 [KW_FUNCT id=1451698947492]
     [java]     at com.goldencode.p2j.pattern.AstWalker.walk(AstWalker.java:274)
     [java]     at com.goldencode.p2j.pattern.AstWalker.walk(AstWalker.java:209)
     [java]     at com.goldencode.p2j.pattern.PatternEngine.apply(PatternEngine.java:1631)
     [java]     at com.goldencode.p2j.pattern.PatternEngine.processAst(PatternEngine.java:1529)
     [java]     at com.goldencode.p2j.pattern.PatternEngine.processAst(PatternEngine.java:1477)
     [java]     at com.goldencode.p2j.pattern.PatternEngine.run(PatternEngine.java:1032)
     [java]     ... 3 more
     [java] Caused by: com.goldencode.expr.ExpressionException: Expression execution error @1:7
     [java]     at com.goldencode.expr.Expression.execute(Expression.java:484)
     [java]     at com.goldencode.p2j.pattern.Rule.apply(Rule.java:491)
     [java]     at com.goldencode.p2j.pattern.Rule.executeActions(Rule.java:738)
     [java]     at com.goldencode.p2j.pattern.Rule.coreProcessing(Rule.java:707)
     [java]     at com.goldencode.p2j.pattern.Rule.apply(Rule.java:530)
     [java]     at com.goldencode.p2j.pattern.RuleContainer.apply(RuleContainer.java:583)
     [java]     at com.goldencode.p2j.pattern.RuleSet.apply(RuleSet.java:98)
     [java]     at com.goldencode.p2j.pattern.AstWalker.walk(AstWalker.java:261)
     [java]     ... 8 more
     [java] Caused by: com.goldencode.expr.ExpressionException: Expression execution error @1:1
     [java]     at com.goldencode.expr.Expression.execute(Expression.java:484)
     [java]     at com.goldencode.p2j.pattern.Rule.apply(Rule.java:491)
     [java]     at com.goldencode.p2j.pattern.Rule.executeActions(Rule.java:738)
     [java]     at com.goldencode.p2j.pattern.Rule.coreProcessing(Rule.java:707)
     [java]     at com.goldencode.p2j.pattern.Rule.apply(Rule.java:530)
     [java]     at com.goldencode.p2j.pattern.NamedFunction.execute(NamedFunction.java:449)
     [java]     at com.goldencode.p2j.pattern.AstSymbolResolver.execute(AstSymbolResolver.java:709)
     [java]     at com.goldencode.p2j.pattern.CommonAstSupport$Library.execLib(CommonAstSupport.java:1262)
     [java]     at com.goldencode.expr.CE107.execute(Unknown Source)
     [java]     at com.goldencode.expr.Expression.execute(Expression.java:391)
     [java]     ... 15 more
     [java] Caused by: com.goldencode.p2j.pattern.CommonAstSupport$UserGeneratedException: Unrecognized return type FUNC_CLASS [KW_FUNCT id <1451698947492> 356:1]
     [java]     at com.goldencode.p2j.pattern.CommonAstSupport$Library.throwException(CommonAstSupport.java:2528)
     [java]     at com.goldencode.p2j.pattern.CommonAstSupport$Library.throwException(CommonAstSupport.java:2513)
     [java]     at com.goldencode.expr.CE126.execute(Unknown Source)
     [java]     at com.goldencode.expr.Expression.execute(Expression.java:391)
     [java]     ... 24 more

During what phase of the ConversionDriver was this reported?

I ask because we do support OO 4GL for the purposes of parsing and for Code Analytics. But we don't yet support OO 4GL for conversion to Java. If this was reported during Annotations or Core Conversion, then it would be expected.

No additional logging is needed. It is clear this is during "Post Parse Fixups" which is part of the front-end. It should work, so this is a bug to fix.

Revision 11178 of branch 3353a contains the fix to this bug. The problem is resolved for the front end. General OO support is not there yet for conversion or runtime.

Branch 3353a was merged to trunk as revision 11187. It will soon be available publicly as FWD v3.2.