[PD] definitions of data types

[Frank Barknecht]

Hallo,
Martin Peach hat gesagt: // Martin Peach wrote:

> Yes but to me
> [1 two three four(
> and
> [one two three four(
> are both lists and pd shouldn't treat them differently as it now does.

And what about [one two three four( and [list one two three four( ?
Should these both be 4-element lists or should one be a 5-element
list? Should "float 2" be a 2-element list or a 1-element number?
Should "symbol foo" be a 2-element list or a 1-element symbol?

Pd currently acts like this: 

"cat Garfield" is one and not two cats.

"mice Micky Minnie" is two and not three mice. 

"list mice Micky Minnie" however are three whatevers of unknown animal
type. [list trim] could convert the three whatevers to two mice named
"Mickey" and "Minnie".

This mechanism allows users to define their own types (of animals) and
still do the same operations on them that they can do on the built-in
types. 

For example using [list] it's possible to make a group of mice and
cats. For this, [list] first internally converts "mice Micky Minnie"
and "cat Garfield" to proper list-messages: "list mice Micky Minnie"
and "list cat Garfield". 

Now all objects, that know how to deal with list-messages but maybe
not with cat- and mice-messages can deal with the combination message:
"list mice Micky Minnie cat Garfield". 

Now try to imagine an animal called "set". It's an almost extinct
reptile living in South America that was once seen there in real live
by Derek Holzer who recorded it and won a prize with that specific
field recording at Transmediale 2005. 

Jus' kidding.

A "set"-animal would totally confuse a lot of objects in Pd, most
notably the [message(-object, but also tabread etc.

However as Pd knows about list-messages, it is no big deal to use such
an animal in your patches, because you just use [list] or something
else to generate a proper list-message and then go on and put lots of
set-animals with various names in cages and start breeding to save
them from extinction. 

Without Pd's use of the list-selector this would be harder to achieve
in such a simple way.

Ciao
-- 
 Frank Barknecht                 _ ______footils.org_ __goto10.org__