[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

bug#2816: regexp-opt: does not optimize 'Abc' and 'abc'

From: Stefan Monnier
Subject: bug#2816: regexp-opt: does not optimize 'Abc' and 'abc'
Date: Sun, 29 Mar 2009 13:13:09 -0400
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/23.0.91 (gnu/linux)

> A)

>     (regexp-opt
>       '("Abc"
>         "abc"))

>     => "\\(?:[Aa]bc\\)"

> B)

>     (regexp-opt
>       '("Abc"
>         "def"
>         "abc"))

>     => "\\(?:Abc\\|abc\\|def\\)"

> Shouldn't regexp-opt optimize B case as well?

The `opt' of regexp-opt should be understood in the sense of
optimization used in compilers, not in the formal mathematical sense of
"optimal".  I.e. it does some effort to improve things, but without any
guarantee about what is and what isn't optimized.

So, yes, it would be good if it did do what you suggest, but it's not
a bug if it doesn't.


reply via email to

[Prev in Thread] Current Thread [Next in Thread]