Hal Fulton wrote:
> Trans wrote:
> > So in a way you are right, it is a kind of two-way inheritance. And if
> > you think about the orgins of Symbol one can more understand why.
> > Symbols did not originally exit in Ruby. They were added later as a
> > light-weight substitute for Strings. So indeed their very existance is
> > one intended to easily interchange depeding on the usage.
>
> When were symbols introduced? I think it was quite some time ago.
> Definitely a 20th-century feature.

Ruby 1.6.0 introduced Symbols in a stable release.

> Who described them as a "lightweight substitute for strings"?

Symbols are more lightweight objects than strings, since they are
immediates like fixnums.

                                                       matz.

> >>I think there's a somewhat exaggerated sense of the speed-up factor
> >>involved in symbols sometimes.
> >
> > That may be the case, but then why have symbols?
>
> They're immutable. They're easier to type. They're singletons in a
> sense, so they save memory.

All good (and lightweight) reasons.

T.