[Python-Dev] Adding NewType() to PEP 484 (original) (raw)
Guido van Rossum guido at python.org
Sat May 28 00:26:29 EDT 2016
- Previous message (by thread): [Python-Dev] Adding NewType() to PEP 484
- Next message (by thread): [Python-Dev] Adding NewType() to PEP 484
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
On Fri, May 27, 2016 at 6:59 PM, Greg Ewing <greg.ewing at canterbury.ac.nz> wrote:
Steven D'Aprano wrote:
TypeAlias? Because A is an alias for int? That suggests it's just another name for the same type, but it's not. It's a distinct type as far as the static type checker is concerned.
We discussed this over dinner at PyCon, some ideas we came up with:
Dependent types, harking back to a similar concept in Ada (https://en.wikibooks.org/wiki/Ada_Programming/Type_System#Derived_types) which in that language is also spelled with "new".
New type
Distinguished Type
Distinguished Subtype
Distinguished Type Alias
Distinguished Alias
BoatyMcBoatType
The nice thing about "distinguished" is that it's a relatively rare word so it is easy to remember or look up.
Personally I'm still in favor of Derived type (but I'm more into ancient programming languages than most folks here). I could also live with Distinguished Type.
The problem with Alias is that these types are not aliases (at least not to the type checker, which is where we need the terminology -- so we can talk about what the type checker does to these).
Fake types? Virtual types? Pseudo-types?
I'm not keen on any of these.
-- --Guido van Rossum (python.org/~guido)
- Previous message (by thread): [Python-Dev] Adding NewType() to PEP 484
- Next message (by thread): [Python-Dev] Adding NewType() to PEP 484
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]