Node:Keyword tuples, Next:Macros, Previous:Tuples, Up:Functions
(NOT IMPLEMENTED!)
Positional parameters correspons to normal tuples. But what about keyword parameters? One possibility is to defined keyword tuples.
An environment is a mapping from a set of names
to values, just like a sequence is a mapping from
(part of) the integers to values.
The tupling operator @ yields a normal tuple
from a sequence; we can also define it to
yield a keyword tuple from an environment.
A keyword parameter name:value
is a keyword tuple (with one element/binding).
There can now be two tuple formals.
The first bundles up the unused positional parameters,
and defines a sequence.
The second (if any) bundles up the keyword parameters,
and defines an environment.
(In addition, there can be a tuple formal for left-hand arguments.)
(If you want no positional parameters, just make the first
tuple formal be []@.)
[x:3 y:4] == (:|x=3; :|y=4).