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Hack request: rational numbers

Pearu Peterson pearu at ioc.ee
Fri Jan 26 06:11:45 EST 2001 
On 25 Jan 2001, Michael Hudson wrote:

> > is rather clumsy. Clearly, minimal representation of this rational number
> > is
> > 
> >     3/4
> > 
> > but in Python this expression has different meaning.
> 
> Here's an idea: subclass code.InteractiveConsole.  Use bytecodehacks
> to find bytecodes like
> 
> LOAD_CONST <integer1>
> LOAD_CONST <integer2>
> BINARY_DIVIDE
> 
> to
> 
> LOAD_GLOBAL "mpq"
> LOAD_CONST <integer1>
> LOAD_CONST <integer2>
> CALL_FUNCTION 2
> 
> This isn't actually very difficult, but I'm not going to do it.

And it will break other codes/modules where `3/4' is expected to return
`0'. And it will work only for interactive session, right?
So, I'll not going to do that either.


> > 3) What are changes that these hooks will be accepted to Python core?
> 
> Can't speak for the people whose opinions really count, but my guess: none.

It is rather disappointing estimation:(

And it makes me think that (some? most?) people want to keep
Python usage only in web/gui based applications rather than extending its
usage to scientific computing (both *numerical* and *symbolical*).

Sorry to bother you.


> > 4) Is anybody else working with builtin rational number support for
> > Python?
> 
> Maybe.  I suspect not enough to make a difference.  It's mooted that 
> 
> 1/2
> 
> will produce something other than "0" in Py3K, but I can't remember
> whether a rational or a floating point result seemed most likely last
> time this went around.

Though, I'll wait (hope) for Alex's PEP about this and I'll probably try
to implement `3r' hooks to Python myself (it's just too appeling to me;).

Regards,
	Pearu
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