From: "Shot (Piotr Szotkowski)" <shot@...>
Date: 2010-01-20T18:44:00+09:00
Subject: Re: Looking for object.inherits?(Classname)

--ikeVEW9yuYc//A+q
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

Robert Klemme:

> irb(main):010:0> a =3D []
> =3D> []

[=E2=80=A6]

> irb(main):015:0> Enumerable =3D=3D=3D a
> =3D> true

> Note that I do not recommend using the test from line 12 as it is
> likely much more inefficient than the other ones.  The test from line
> 15 is especially suited for use with "case" statements as in

> case a
> when Enumerable
>   puts "it's enumerable"
> when Array, Hash
>   puts "It's a special enumerable"
> when Integer
>   puts "You can count on me."
> else
>   puts "No idea about a."
> end

A minor nitpick: Note that due to case=E2=80=99s behaviour (once a =E2=80=
=98when=E2=80=99
matches, other =E2=80=98whens=E2=80=99 are ignored), the above will almost =
never=C2=B9
print =E2=80=98It's a special enumerable=E2=80=99, as Arrays and Hashes are=
 almost
always=C2=B9 Enumerable. Testing for Array/Hash first and Enumerable
second would make more sense in most cases.

=C2=B9 you can redefine any constant, so you could redefine what
Array and Hash mean, but usually it=E2=80=99s a rather bad idea

=E2=80=94 Shot
--=20
You can write good programs in PHP, but the language does not support it.
                                                            [Karol Kozub]

--ikeVEW9yuYc//A+q
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: Digital signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEARECAAYFAktW0FwACgkQi/mCfdEo8UqcAQCeJf3HFrgjB31RoyH8/dK8Tk/S
YxMAn0cg8sLWmdN6kC8KKmM3tWNDgSSk
=1sF4
-----END PGP SIGNATURE-----

--ikeVEW9yuYc//A+q--