Re: [boost] The 'head' and 'tail' of a type list

From: joel de guzman (djowel_at_[hidden])
Date: 2001-12-04 17:21:30

----- Original Message ----- 
From: "Andrei Alexandrescu" :

> > Andrei Alexandrescu [andrewalex_at_[hidden]] wrote:
> > > From: "Geurt Vos" <G.Vos_at_[hidden]>
> > > > Can anyone explain why the members of the type list
> > > > template are called 'head' and 'tail'? I mean the
> > > > type list template is merely a node in a linked list
> > > > of types, where 'head' represents the content of the
> > > > node, and 'tail' points to the next node.
> > >
> > > Typelists are much like well-formed LISP-lists, in which "head" is
> > > an "atomic type" (non-typelist) and tail is actually another list,
> > > or nil. So "next" would not be a good choice. Besides, head and tail
> > > are quite consecrated for denoting this type of list.
> > >
> > > I don't think anyone would have liked 'car' and 'cdr' :o).
> >
> > How about 'first' and 'rest'?
> 
> Why gratuitously invent new terminology when there's terminology in place
> that's well known.

Unless it's too cryptic like car and cdr :-)

--Joel