Fix to allow using Smalltalk blocks even after the method containing

their definition has returned.


git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/steptalk/trunk@36420 72102866-910b-0410-8b05-ffd578937521

Languages/Smalltalk/ChangeLog

@@ -1,3 +1,19 @@
+2013-03-24  Wolfgang Lux  <wolfgang.lux@gmail.com>
+
+    * STExecutionContext.h: Change type of instruction pointer attribute
+    to NSUInteger.
+    * STExecutionContext.m (-invalidate, -isValid): Invalidate an
+    execution context by setting its instruction pointer to NSNotFound.
+
+    * STMethodContext.m (-invalidate, -isValid):
+    * STBlockContext.m (-invalidate, -isValid): Delete method
+    implementations so that the method and home context attributes of a
+    method context and block context, respectively, are not destroyed when
+    the method or block returns.
+
+    Together these changes make it possible to use blocks even after the
+    method containing their definition has returned.
+
 2013-03-24  Wolfgang Lux  <wolfgang.lux@gmail.com>
 
     * Externs.h (STInterpreterReturnException):

Languages/Smalltalk/STBlockContext.m

@@ -66,14 +66,6 @@
 {
     return homeContext;
 }
-- (void)invalidate
-{
-    [self setHomeContext:nil];
-}
-- (BOOL)isValid
-{
-    return [homeContext isValid];
-}
 
 - (unsigned)initialIP
 {

Languages/Smalltalk/STExecutionContext.h

@@ -33,7 +33,7 @@
     
     STStack            *stack;
     
-    unsigned            instructionPointer;
+    NSUInteger          instructionPointer;
 }
 - initWithStackSize:(unsigned)stackSize;
 

Languages/Smalltalk/STExecutionContext.m

@@ -53,12 +53,11 @@ static unsigned nextId = 1;
 }
 - (void)invalidate
 {
-    [self subclassResponsibility:_cmd];
+    instructionPointer = NSNotFound;
 }
 - (BOOL)isValid
 {
-    [self subclassResponsibility:_cmd];
-    return NO;
+    return (instructionPointer != NSNotFound);
 }
 - (unsigned)instructionPointer
 {

Languages/Smalltalk/STMethodContext.m

@@ -89,16 +89,6 @@
                 format:@"Should not set home context of method context"];
 }
 
-- (void)invalidate
-{
-    RELEASE(method);
-    method = nil;
-}
-- (BOOL)isValid
-{
-    return (method != nil);
-}
-
 - (STCompiledMethod*)method
 {
     return method;