mechvel:
> On Mon, Apr 26, 2004 at 04:06:22PM +0100, Philippa Cowderoy wrote:
> > On Mon, 26 Apr 2004, Serge D. Mechveliani wrote:
> >
> > > Alexander is right.
> > >
> > > Also as Integer has more sense than Int,
> > >
> >
> > To ask a silly question, is Int defined as 32 bits or is it defined in a
> > similar vein to C's int?
Well, you can all look this up, at least in GHC's implementation:
$fptools/libraries/base/GHC/Base.lhs:
data Int = I# Int#
-- ^A fixed-precision integer type with at least the range @[-2^29
-- .. [EMAIL PROTECTED] The exact range for a given implementation can be
-- determined by using 'minBound' and 'maxBound' from the 'Bounded'
-- class.
$fptools/ghc/compiler/prelude/primops.txt.pp:
section "The word size story."
{Haskell98 specifies that signed integers (type {\tt Int})
must contain at least 30 bits. GHC always implements {\tt
Int} using the primitive type {\tt Int\#}, whose size equals
the {\tt MachDeps.h} constant {\tt WORD\_SIZE\_IN\_BITS}.
This is normally set based on the {\tt config.h} parameter
{\tt SIZEOF\_HSWORD}, i.e., 32 bits on 32-bit machines, 64
bits on 64-bit machines. However, it can also be explicitly
set to a smaller number, e.g., 31 bits, to allow the
possibility of using tag bits. Currently GHC itself has only
32-bit and 64-bit variants, but 30 or 31-bit code can be
exported as an external core file for use in other back ends.
...
#if WORD_SIZE_IN_BITS < 32
#define INT32 Int32#
#define WORD32 Word32#
#else
#define INT32 Int#
#define WORD32 Word#
#endif
#if WORD_SIZE_IN_BITS < 64
#define INT64 Int64#
#define WORD64 Word64#
#else
#define INT64 Int#
#define WORD64 Word#
#endif
-- Don
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