Add pub const fn default() for various types. - #9929
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ErichDonGubler
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This broadly LGTM, and does what it says it does. Just want to ping at least one other @gfx-rs/wgpu member for their thoughts/approval before we merge this API addition (which I don't want to wait longer than a couple of days for, unless you feel strongly, @kpreid).
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Leaving unmerged in case the latest feedback made you want to edit something. Otherwise: fire when ready! |
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Pushed 1 doc edit. Should be good to merge now. |
The default functions are generated using a `macro_rules_attribute` emulated derive macro, just fancy enough to work. It does not support structs with generics, so `*Descriptor`s are left alone for now. When Rust const traits stabilize, we can replace this with real const traits.
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Rebased with resolved conflicts in the |
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August 3, 2026 10:11
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Fixes #9923.
Description
Allows use of
wgpu’s provided default values for its types in dependents’ constant evaluation.The default functions are generated using a
macro_rules_attributeemulated derive macro, just fancy enough to work. It does not support structs with generics, so*Descriptors are left alone for now.ConstDefaultHelperis not part of the public API.Separately,
ForceShaderModelToken::{with_shader_model, get}are nowconst fn.DxcShaderModelnow implementsCopy.Testing
Existing tests pass. But perhaps we should also add a test or doctest showing that this constant works. Where?
Squash or Rebase?
Rebase
Checklist
wgpumay be affected behaviorally.CHANGELOG.mdentries for the user-facing effects of this change are present.