Re: [EXTERN] Re: Re: Definition of tokens in GP language

[Hong-Phuc Bui <hong-phuc.bui@htwsaar.de>]

Before I try to do something impossible: did someone try to rewrite the lexer in lex?


On 24/10/2025 23:32, Bill Allombert wrote:
> On Fri, Oct 24, 2025 at 09:59:38PM +0200, Hong-Phuc Bui wrote:
> > Hi Bill,
> >
> > I took a look at the function. It is not really long, but I'm not sure about complexity:
> > Is it possible to recognize all tokens of GP by using regular express?
>
> Strictly speaking it is not possible using regex due to ambiguities.
> For example
> 3!=6  is  3 != 6   (3 tokens)
> while
> 3!==6 is  3 ! == 6 (4 tokens)
> and
> 3!===6 is  3 ! === 6 (4 tokens)
>
> There are other corner cases, depending how you define a token.
>
> Note that all spaces are removed before parsing so for example
> a ! = b  is a != b (3 tokens)
>
> Cheers,
> Bill.

--
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