Re: QUIT and ABORT

On 6/05/2025 3:29 am, Ruvim wrote:

On 2025-05-05 08:11, dxf wrote:

...
However modifying it to do so gives these results:
>
1 .( a ) cr -56 throw .( b )
>
   'a' is displayed and the stack is: 1

 
This violates the behavior of `throw` specified in 9.6.1.2275,
because if there is no a user's exception frame, the data stack must be emptied.
 
The table 9.1 in Forth-2012 (or 9.2 in Forth-94) does not affect the behavior of `throw` at all.
 
Your implementation will probably fail the following test case:
 
  t{ 123 [: 999 -56 throw ;] catch 456 -> 123 -56 456 }t

For that I get:

123 -56 456

: bar 4 quit ; ' bar catch 6
>
   stack is: -56 6
>

 
This violates `quit` 6.1.2050, because:
  - `quit` is not allowed to remove anything from the data stack (in this case, remove 4 from the stack);
  - `quit` is not allowed to place anything on the data stack (in this case, place `-56`);
  - `quit` is not allowed to interpret the remaining part of the input buffer  (in this case, interpret "6" and place 6 on the stack).

A caught ABORT does the same:

SwiftForth i386-Win32 3.11.9-RC1 01-Sep-2022

: bar 4 abort ; ' bar catch 6 .s
-1 6 <-Top  ok