Preliminary typechecking version of objj_msgSend, and preprocessor support.

Objective-J/preprocess.js

@@ -578,12 +578,15 @@ objj_preprocessor.prototype.method = function(tokens)
     var buffer = new objj_stringBuffer(),
         token,
         selector = "",
-        parameters = [];
+        parameters = [],
+        types = [null];
     
     while((token = tokens.skip_whitespace()) && token != TOKEN_OPEN_BRACE)
     {
         if (token == TOKEN_COLON)
         {
+            var type = "";
+
             // Colons are part of the selector name
             selector += token;
             
@@ -592,18 +595,30 @@ objj_preprocessor.prototype.method = function(tokens)
             if (token == TOKEN_OPEN_PARENTHESIS)
             {
                 // Swallow parameter/return type.  Perhaps later we can use this for debugging?
-                while((token = tokens.skip_whitespace()) && token != TOKEN_CLOSE_PARENTHESIS) ;
+                while((token = tokens.skip_whitespace()) && token != TOKEN_CLOSE_PARENTHESIS)
+                    type += token;
     
                 token = tokens.skip_whitespace();
             }
             
+            // Add the type. If it's empty, add null instead.
+            types[parameters.length+1] = type || null;
+
             // Since this follows a colon, this must be the parameter name.
             parameters[parameters.length] = token;
         }
         
         else if (token == TOKEN_OPEN_PARENTHESIS)
+        {
+            var type = "";
+
             // Since :( is handled above, this must be the return type, just swallow it.
-            while((token = tokens.skip_whitespace()) && token != TOKEN_CLOSE_PARENTHESIS) ;
+            while((token = tokens.skip_whitespace()) && token != TOKEN_CLOSE_PARENTHESIS)
+                type += token;
+
+            // types[0] is the return argument
+            types[0] = type || null;
+        }
         
         // Argument list ", ..."
         else if (token == TOKEN_COMMA)
@@ -640,7 +655,7 @@ objj_preprocessor.prototype.method = function(tokens)
 
     CONCAT(buffer, ")\n{ with(self)\n{");
     CONCAT(buffer, this.preprocess(tokens, NULL, TOKEN_CLOSE_BRACE, TOKEN_OPEN_BRACE));
-    CONCAT(buffer, "}\n})");
+    CONCAT(buffer, "}\n},"+types.toSource()+")");
 
     return buffer;
 }

Objective-J/runtime.js

@@ -542,3 +542,84 @@ function sel_registerName(aName)
 {
     return aName;
 }
+
+
+// Type checking version of objj_msgSend:
+
+function objj_msgSendTypeCheck(/*id*/ aReceiver, /*SEL*/ aSelector)
+{
+    if (aReceiver == nil)
+        return nil;
+
+    CLASS_GET_METHOD_IMPLEMENTATION(var implementation, aReceiver.isa, aSelector);
+
+    var types = method.types;
+
+    for (var i = 2; i < arguments.length; i++)
+    {
+        try
+        {
+            runtimeTypeCheck(types[i-1], arguments[i]);
+        }
+        catch (e)
+        {
+            objj_fprintf(warning_stream, "Type check failure: "+
+                "aReceiver="+String(aReceiver).substring(0,100)+", "+
+                "aSelector="+String(aSelector).substring(0,100)+", "+
+                "argument #"+(i-2)+": " + e);
+        }
+    }
+
+    var result = implementation.apply(aReceiver, arguments);
+
+    try
+    {
+        runtimeTypeCheck(types[0], result);
+    }
+    catch (e)
+    {
+        objj_fprintf(warning_stream, "Type check failure: "+
+            "aReceiver="+String(aReceiver).substring(0,100)+", "+
+            "aSelector="+String(aSelector).substring(0,100)+", "+
+            "return value: " + e);
+    }
+
+    return result;
+}
+
+function runtimeTypeCheck(typeName, actual)
+{
+    var objjClass;
+
+    if (!typeName)
+    {
+        return;
+    }
+    if (typeName === "id")
+    {
+        return;
+    }
+    else if (typeName === "void")
+    {
+        if (actual === undefined)
+            return;
+    }
+    else if (objjClass = objj_getClass(typeName))
+    {
+        if (actual && actual.isa)
+        {
+            var theClass = actual.isa;
+            for(; theClass; theClass = theClass.super_class)
+            if (theClass === objjClass)
+                return;
+        }
+    }
+    else
+    {
+        return;
+    }
+
+    throw("Expected " + typeName + ", was [" + actual +"]");
+}
+
+objj_msgSend = objj_msgSendTypeCheck;