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Diff for /gforth/doc/gforth.ds between versions 1.165 and 1.166

version 1.165, 2006/10/25 22:01:17 version 1.166, 2006/10/27 21:47:01
Line 650  are given. Line 650  are given.
 In addition to the @command{gforth} engine, there is also an engine  In addition to the @command{gforth} engine, there is also an engine
 called @command{gforth-fast}, which is faster, but gives less  called @command{gforth-fast}, which is faster, but gives less
 informative error messages (@pxref{Error messages}) and may catch some  informative error messages (@pxref{Error messages}) and may catch some
 stack underflows later or not at all.  You should use it for debugged,  errors (in particular, stack underflows and integer division errors)
   later or not at all.  You should use it for debugged,
 performance-critical programs.  performance-critical programs.
   
 Moreover, there is an engine called @command{gforth-itc}, which is  Moreover, there is an engine called @command{gforth-itc}, which is
Line 2140  Usually the name of a definition is not Line 2141  Usually the name of a definition is not
 earlier definitions are usually visible:  earlier definitions are usually visible:
   
 @example  @example
 1 0 / . \ "Floating-point unidentified fault" in Gforth on most platforms  1 0 / . \ "Floating-point unidentified fault" in Gforth on some platforms
 : / ( n1 n2 -- n )  : / ( n1 n2 -- n )
   dup 0= if    dup 0= if
     -10 throw \ report division by zero      -10 throw \ report division by zero
Line 12925  characters are matched case-sensitively. Line 12926  characters are matched case-sensitively.
   
 @item division rounding:  @item division rounding:
 @cindex division rounding  @cindex division rounding
 installation dependent. @code{s" floored" environment? drop .}. We leave  The ordinary division words @code{/ mod /mod */ */mod} perform floored
 the choice to @code{gcc} (what to use for @code{/}) and to you (whether  division (with the default installation of Gforth).  You can check
 to use @code{fm/mod}, @code{sm/rem} or simply @code{/}).  this with @code{s" floored" environment? drop .}.  If you write
   programs that need a specific division rounding, best use
   @code{fm/mod} or @code{sm/rem} for portability.
   
 @item values of @code{STATE} when true:  @item values of @code{STATE} when true:
 @cindex @code{STATE} values  @cindex @code{STATE} values
Line 12939  On two's complement machines, arithmetic Line 12942  On two's complement machines, arithmetic
 arithmetic (with appropriate mapping for signed types). Division by  arithmetic (with appropriate mapping for signed types). Division by
 zero typically results in a @code{-55 throw} (Floating-point  zero typically results in a @code{-55 throw} (Floating-point
 unidentified fault) or @code{-10 throw} (divide by zero).  Integer  unidentified fault) or @code{-10 throw} (divide by zero).  Integer
 division overflow can result in these throws, or in @code{-11 throw}.  division overflow can result in these throws, or in @code{-11 throw};
   in @code{gforth-fast} division overflow and divide by zero may also
   result in returning bogus results without producing an exception.
   
 @item whether the current definition can be found after @t{DOES>}:  @item whether the current definition can be found after @t{DOES>}:
 @cindex @t{DOES>}, visibility of current definition  @cindex @t{DOES>}, visibility of current definition
Line 13045  These are located in writable memory and Line 13050  These are located in writable memory and
 @cindex result out of range  @cindex result out of range
 On two's complement machines, arithmetic is performed modulo  On two's complement machines, arithmetic is performed modulo
 2**bits-per-cell for single arithmetic and 4**bits-per-cell for double  2**bits-per-cell for single arithmetic and 4**bits-per-cell for double
 arithmetic (with appropriate mapping for signed types). Division by zero  arithmetic (with appropriate mapping for signed types). Division by
 typically results in a @code{-10 throw} (divide by zero) or @code{-55  zero typically results in a @code{-10 throw} (divide by zero) or
 throw} (floating point unidentified fault). @code{convert} and  @code{-55 throw} (floating point unidentified fault). Overflow on
   division may result in these errors or in @code{-11 throw} (result out
   of range).  @code{Gforth-fast} may silently produce bogus results on
   division overflow or division by zero.  @code{Convert} and
 @code{>number} currently overflow silently.  @code{>number} currently overflow silently.
   
 @item reading from an empty data or return stack:  @item reading from an empty data or return stack:
Removed from v.1.165  
changed lines
  Added in v.1.166

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