>From the MVEL docs (http://mvel.codehaus.org/MVEL+2.0+Typing): Strict Typing Strict typing in MVEL is an optional mode for the compiler, in which all types must be fully qualified, either by declaration or inference. Enabling Strict Mode When compiling an expression, the compiler can be put into strict mode through the ParserContext by setting setStrictTypeEnforcement(true). Satisfying type strictness can be accomplished both by requiring explicit declaration of types inside the expression, or by notifying the parser ahead of time of what the types of certain inputs are. For example: ExpressionCompiler compiler = new ExpressionCompiler(expr); ParserContext context = new ParserContext(); context.setStrictTypeEnforcement(true); context.addInput("message", Message.class); context.addInput("person", Person.class); compiler.compile(context); In this example we inform the compiler that this expression will be accepting two external inputs: message and person and what the types of those inputs are. This allows the compiler to determine if a particular call is safe at compile time, instead of failing at runtime. Note about Generic Types You must use Strong Typing Mode to enable awareness of generic types. Type parameters for collections and other types will not be visible in strict-typing mode alone. Strong Typing Strong typing is a newly introduced mode in MVEL 2.0. It is different from strict mode in the sense that strongly typed mode requires that all variables be type qualified. Contrast this with strict mode which only requires that properties and method calls be qualified at compile-time. See the full article: Strong Typing Mode -- View this message in context: http://drools-java-rules-engine.46999.n3.nabble.com/MVEL-strict-mode-when... Sent from the Drools - User mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users