Karim BELABAS on Tue, 2 Mar 1999 11:50:13 +0100 (MET)

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Re: Strange polresultant behavior

[Peter Montgomery wrote:]
>         By the way, why are blanks removed in echo mode?  
> My input to this example was
> \e
> f1 = x*y - 1
> f2 = x*y - 2
> polresultant(f1, f2, x)

Because what is echoed is the final sequence sent to the parser proper, after
all preprocessinghas been done  (getting rid of blanks, special editing
characters, ...)

It was slightly easier to program this way. The alternative would be to split
the preprocessing in 2 and filter out blancks and special characters once the
(multi-)line has been entirely input. [Note: Version 1.39.15 printed each
line immediately after it was entered, which was quite annoying for
multi-line input.]

The latter would be a bit cleaner, but more cumbersome and requires some more
copying/parsing, which could become a problem for large files. I don't feel
strongly either way, but I guess I'm going to stick with the current

Karim Belabas                    email: Karim.Belabas@math.u-psud.fr
Dep. de Mathematiques, Bat. 425
Universite Paris-Sud             Tel: (00 33) 1 69 15 57 48
F-91405 Orsay (France)           Fax: (00 33) 1 69 15 60 19
PARI/GP Home Page: http://hasse.mathematik.tu-muenchen.de/ntsw/pari/