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From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: comp.theory
Subject: Re: Real Number --- Merely numbers whose digits can be infinitely long
Date: Wed, 01 May 2024 22:58:50 +0100
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wij <wyniijj5@gmail.com> writes:

> Got your idea.

It's not my idea.  It's a standard notation.

> I'll try use '|' exclusively. Thanks for the suggestions:
>
>      <fixed_point_number>::= [-] <wnum> [ . <frac> ]  // excluding "-0" case
>      <wnum>::= 0
>      <wnum>::= <nzd> { 0 | <nzd> }
>      <frac>::= { 0 | <nzd> } <nzd>
>      <nzd> ::= 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 // 'digit' varys depending on n-ary
>
>     Ex: 78, -12.345, 3.1414159

So what's the point of defining these strings that represent a subset of
the rationals?

-- 
Ben.