onOverride_afterResTypes_semAn_afterSemAn

OnOverride_afterResTypes_semAn_afterSemAn.cyan

package metaobjectTest


@doc{*
    Annotations of this metaobject should be attached to a method. 
    The attached DSL code is made in Myan, which supports interpreted Cyan
    within parameterless methods declared with 'func': 
    
        func afterResTypes_codeToAdd {    
            // interpreted Cyan code
        }
    
    According to the method name, the Cyan code is interpreted in phase
    afterResTypes or semAn. Methods of interfaces
        IAction_semAn
        IActionNewPrototypes_semAn
        IAction_afterResTypes
        IActionNewPrototypes_afterResTypes
        IParseWithCyanCompiler_dpa 
        ICommunicateInPrototype_afterResTypes_semAn_afterSemAn    
        IActionMethodMissing_semAn
        ICheckOverride_afterSemAn
        
    can be implemented. To better understand this, see the documentation 
    for action_afterResTypes_semAn.
*}
open
object OnOverride_afterResTypes_semAn_afterSemAn

    func run {
    
        // a compilation warning with a custom error message
        self selfTest;
        
        // if uncommented, a regular compilation error
        // self alienMethod;    
    }
    
    @onOverride_afterResTypes_semAn_afterSemAn{*
        // replace all keyword messages (without a declared method)
        // with more than 3 keywords by 0
        // Since this annotation is attached to a unary method,
        // this method is not really used. Demonstration only.
        func semAn_missingKeywordMethod {
        
            let Int size = message getkeywordParameterList size;
            if size > 3 {
                var aType = env searchPackagePrototype: "cyan.lang", "Int";
                return [. "0", aType .];
            }
        }


        // an warning message for unary message passings
        // ending with 'Test'
        // It is necessary to return, in this case, an expression 
        // that replaces the message passing. Otherwise the 
        // compiler will issue an error
        func semAn_missingUnaryMethod {
            var String name = unarySymbol getSymbolString;
            if name endsWith: "Test" {
                Out println: "Methods ending with 'draw' have not been implemented yet";
                return [. "JavaInterop nop", "cyan.lang", "Nil" .];
            }
        }
        
        // only prototypes whose names start with 'Sub' can override 
        // this method. A message is printed, but no error is issued
        func afterSemAn_checkOverride {
            let String subProtoName = method getDeclaringObject getName;
            let String methodName = method getName;
            if !(subProtoName startsWith: "Sub") {
                Out println: "I am really sorry, but method " ++
                   methodName ++ " can only be overridden in prototypes whose name " ++
                   "start with 'Sub'";
            }
        }
    *}
    func draw {
    }

    
end