Karim Belabas on Sat, 09 Mar 2013 17:42:05 +0100


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Re: PARI 2.6 syntax 2: [f(x)|x<-a,b(x)]


* Joerg Arndt [2013-03-09 17:21]:
> * Andreas Enge <andreas.enge@inria.fr> [Mar 09. 2013 09:12]:
> > On Fri, Mar 08, 2013 at 01:41:15PM +0100, Bill Allombert wrote:
> > > Space are ignored, so 'x in a' is read as 'xina'.
> > 
> > This might be a good occasion to declare spaces as significant in the
> > lexical analysis step...
> 
> If at all possible, let's *please* do this.
> > It would break backwards compatibility, but are
> > there really people who write
> > a
> > 
> > b   =
> > 1 2
> > when they mean
> > ab=12
> > ?
> 
> Possibly a subset of the folks that hammer nails
> into their knees in their spare time.

I see one potential use, for large constants. Here's a (silly) Maple session

> 2^1000;
107150860718626732094842504906000181056140481170553360744375038837035105112\
    49361224931983788156958581275946729175531468251871452856923140435984577\
    57469857480393456777482423098542107460506237114187795418215304647498358\
    19412673987675591655439460770629145711964776865421676604298316526243868\
    37205668069376

I can currently copy-paste this directly into GP. This will break if spaces
become significant.

I don't care that much [ in fact, not at all: 1) I don't use Maple, 2) I can
write trivial scripts in seconds to filter input to my liking :-) ], but it
can be a significant problem for some users.

Cheers,

    K.B.
--
Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
Universite Bordeaux 1          Fax: (+33) (0)5 40 00 69 50
351, cours de la Liberation    http://www.math.u-bordeaux1.fr/~belabas/
F-33405 Talence (France)       http://pari.math.u-bordeaux1.fr/  [PARI/GP]
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