Re: Help with Meridian compiler, please

[darwin.sura.net!sgiblab!news.cs.indiana.edu!arizona.edu!east.pima.edu!rha]

In article <1993Feb4.144224.7460@goya.uu.es>, aalvarez@dit.upm.es 
(Angel Alvarez) writes:
> The following simple program fails to compile with the PC Meridian compiler
> (both 286 and 386):
> 
> procedure w is
>   a: NATURAL range 0..1:=0;
> begin
>   null;
> end w;

Never quite saw this one before!  The hint is in the actual error message
generated (which often is helpful to include when posting to such a wide
audience):  "illegal base in numeric literal".  Understanding the source of the
error is not trivial!  First, you must remember from LRM 2.10/3 that "sharp
characters (#) of a based literal can be replaced by colons (:)...".  The
compiler "thinks" you are about to supply a based literal as the endpoint of
the range, perhaps something like 16#FFF#, only you've "chosen" to substitute
colons like 16:FFF: .  The lexer probably doesn't look FIRST for the entire
syntactic construct for a based literal before deciding that it really IS what
you intended.

Next time I'm on the phone with them, I'll pass this along!
-----
Ray Harwood           |Data Basix           |Adjunct Faculty, East Campus,
Voice: (602)721-1988  |PO Box 18324         |   Pima Community College
FAX:   (602)721-7240  |Tucson, AZ 85731     |Instructor in Ada and Pascal
CompuServe: 76645,1370|AppleLink: DATA.BASIX|Internet: rharwood@east.pima.edu