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From: "G.B." <bauhaus@futureapps.invalid>
Newsgroups: comp.lang.ada
Subject: Re: OpenToken: Parsing Ada (subset)?
Date: Tue, 16 Jun 2015 16:13:46 +0200
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Date: 2015-06-16T16:13:46+02:00
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On 16.06.15 15:24, Dmitry A. Kazakov wrote:
>> It does not enforce all the lexical rules for numbers; it allows
>> >repeated, leading, and trailing underscores; it doesn't enforce pairs of
>> >'#'.
> That is exactly the point. It does not parse literal right and you have to
> reparse the matched chunk of text once again. What was the gain? Why
> wouldn't do it right in single step?

(I believe the use case here permits simplifications,
meaning that REs are not being used for meticulous, final
parsing of Ada.)

But '_' seems missing from "[-+0-9a-fA-F.]+". (And obsolete
Ada syntax, i.e. substitutes for '#'. Which makes a CFG
parser more desirable if '#' or ':' should have matching
occurrences. ;-)