On Feb 7, 2013, at 5:15 PM, Eric Hodel wrote:

> On Feb 7, 2013, at 10:43, David MacMahon <davidm / astro.berkeley.edu> =
wrote:
>> I think the number of real world uses of something like:
>>=20
>> {:a =3D> 0, 'a' =3D> 1}
>>=20
>> is likely to be very small.
>=20
> Every time you run `gem` you use a hash that contains both symbol and =
string keys used for different purposes.
>=20
> In ~/.gemrc symbols are used for configuration options while strings =
are used for command default arguments.

Well, that's one!  In my defense, one is a very small number even if =
that one is of very large consequence. :-)

Just to play Devil's advocate, could that not be separated into two =
different hashes: one for config options and one for command default =
arguments?  You have given semantic meaning to (the class of) the key.  =
Isn't that akin to treating the primary key of a database record in a =
non-opaque manner?

Dave