dev call 20221201

Dev Call: 1 December 2022

Present

Stepan, Mohaned, Tim, Florian, Simon, Matti

Agenda

• Next release 0.9: We need to decide on a few things
  • Issue 343: Use fixed-width integers in the ABI.
  • Issue 354: Use Python class names for context handles.
  • Issue 355: Make expected encoding of C strings explicit.
  • The bytes / string builder API is a possible project for interns. It won't certainly make it into 0.9.
  • Issue 386: Add HPy<type>_Check for all fast equivalent type checks in CPython.
• Decide on PRs:
  • Debug mode: Check correct context usage
  • HPy ABI version verification
  • Exact type checks with HPy_TypeCheck
  • Multi-phase module init
  • Module-state support
• Merged PRs:
  • Enable slots HPy_tp_str and HPy_tp_hash.
  • HPyBytes_AsString should return const char pointer.
  • Make HPy compatible with Python 3.11
  • Introduce Capsule API
  • Improve API/implementation for HPyCapsule_Destructor
  • Add some more built-in types/objects to context
  • Introduce HPy_DelAttr(_s) and HPy_DelItem(_i/_s)
  • Introduce HPy trace mode
  • Use CPython FASTCALL to optimise hpy function call
  • Introduce the Hybrid ABI
• Status updates

Release 0.9

• Issue 343: Yes, let's do that. At least use int64_t for long.
• Issue 354
  • There is a philosophy of being more Python-ish. So, it would make sense to change the name.
  • From the easy migration-path perspective, it is not preferable.
  • Decision: we are more a C-level API, so we keep the C-level naming style.
• Issue 355: Just do it.
• Issue 274: there is a preference to fully implement it on HPy. We can just copy the code from CPython (and maybe from MUSL Libc).
• Issue 386: Let's first try to optimize existing impl and revisit if that isn't enough.

• Multi-phase module init:

  Main problem: CPython implementation seems to be hacked on top of existing code for backwards compatibility. We can do more meaningful stuff. In particular: don't use the module def.

• Module-state support: is bascially ready but we might consider introducing a new calling convention that gives access to the class and indrectly to the module.