Re: A question about regexes

On Sun, 07 Oct 2007 04:47:25 +0200, Altu <altu59@xxxxxxxxx> wrote:

Hi

In Java, the following regex:

"a.b"

matches any string that starts with a then any character and then b.

I am trying to create a DFATable for regexes that are in that format.
However the algorithms in the compiler book I have, only support
cases like:

a[a|b]b

but the problem is that the set of allowed symbols are not confined to
a and b in my language.

Is there an equivalent of "a.b" available that is expressible only
using
concatenation, or, and *?

It's a[a|b|c|...]b

where the [...] ranges over all the characters of your alphabet.
Which, depending on the formalism/conventions/... you use for describing your DFA may or may not be "summed up" (eg a transition with no label which consume any one letter, ...)


--
Hypocoristiquement,
Jym.
.

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