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Diff for /gforth/except.fs between versions 1.9 and 1.16

version 1.9, 2003/11/23 22:52:29 version 1.16, 2007/02/18 17:57:12
Line 1 Line 1
 \ catch, throw, etc.  \ catch, throw, etc.
   
 \ Copyright (C) 1999,2000,2003 Free Software Foundation, Inc.  \ Copyright (C) 1999,2000,2003,2006 Free Software Foundation, Inc.
   
 \ This file is part of Gforth.  \ This file is part of Gforth.
   
Line 20 Line 20
   
 \ !! use a separate exception stack?           anton  \ !! use a separate exception stack?           anton
   
 \ user-definable rollback actions  
   
 Defer 'catch  
 Defer 'throw  
   
 ' noop IS 'catch  
 ' noop IS 'throw  
   
 \ has? backtrace [IF]  \ has? backtrace [IF]
 Defer store-backtrace  Defer store-backtrace
 ' noop IS store-backtrace  ' noop IS store-backtrace
Line 76  Defer store-backtrace Line 68  Defer store-backtrace
   
 \ !! explain handler on-stack structure  \ !! explain handler on-stack structure
   
   Variable first-throw
   : nothrow ( -- ) \ gforth
       \G Use this (or the standard sequence @code{['] false catch drop})
       \G after a @code{catch} or @code{endtry} that does not rethrow;
       \G this ensures that the next @code{throw} will record a
       \G backtrace.
       first-throw on ;
   
 : (try) ( ahandler -- )  : (try) ( ahandler -- )
       first-throw on
     r>      r>
     swap >r \ recovery address      swap >r \ recovery address
     rp@ 'catch >r  
     sp@ >r      sp@ >r
     fp@ >r      fp@ >r
     lp@ >r      lp@ >r
     handler @ >r      handler @ >r
     rp@ handler !      rp@ handler !
     backtrace-empty on  
     >r ;      >r ;
   
 : try ( compilation  -- orig ; run-time  -- ) \ gforth  : try ( compilation  -- orig ; run-time  -- ) \ gforth
Line 100  Defer store-backtrace Line 99  Defer store-backtrace
     rdrop \ lp      rdrop \ lp
     rdrop \ fp      rdrop \ fp
     rdrop \ sp      rdrop \ sp
     r> rp!  
     rdrop \ recovery address      rdrop \ recovery address
     >r ;      >r ;
   
 : recover ( compilation  orig1 -- orig2 ; run-time  -- ) \ gforth  : recover ( compilation  orig1 -- orig2 ; run-time  -- ) \ gforth
     \ !! check using a special tag      \ !! check using a special tag
     POSTPONE (recover)  
     POSTPONE else      POSTPONE else
     docol: here 0 , 0 , code-address! \ start a colon def       docol: here 0 , 0 , code-address! \ start a colon def 
     postpone rdrop                    \ drop the return address      postpone rdrop                    \ drop the return address
 ; immediate compile-only  ; immediate compile-only
   
 : endtry ( compilation  orig -- ; run-time  -- ) \ gforth  : endtry ( compilation  orig -- ; run-time  -- ) \ gforth
     POSTPONE then ; immediate compile-only      POSTPONE then
       POSTPONE (recover)
   ; immediate compile-only
   
 :noname ( x1 .. xn xt -- y1 .. ym 0 / z1 .. zn error ) \ exception  :noname ( x1 .. xn xt -- y1 .. ym 0 / z1 .. zn error ) \ exception
     try      try
Line 126  is catch Line 125  is catch
 :noname ( y1 .. ym error/0 -- y1 .. ym / z1 .. zn error ) \ exception  :noname ( y1 .. ym error/0 -- y1 .. ym / z1 .. zn error ) \ exception
     ?DUP IF      ?DUP IF
         [ here forthstart 9 cells + ! ]          [ here forthstart 9 cells + ! ]
         store-backtrace          first-throw @ IF
               store-backtrace error-stack off
               first-throw off
           THEN
         handler @ ?dup-0=-IF          handler @ ?dup-0=-IF
             >stderr cr ." uncaught exception: " .error cr              >stderr cr ." uncaught exception: " .error cr
             2 (bye)              2 (bye)
 \           quit  \           quit
         THEN          THEN
         rp!          dup rp!
         r> handler !          rdrop
         r> lp!          r> lp!
         r> fp!          r> fp!
         r> swap >r sp! drop r>          r> -rot 2>r sp! drop 2r>
         rdrop 'throw r> perform          r@ swap rp! perform
     THEN ;      THEN ;
 is throw  is throw
   
Removed from v.1.9  
changed lines
  Added in v.1.16

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