Default args for nested inductive constructors

[JamesGallicchio]

Prerequisites

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Description

For nested inductive types, any nested-inductive arguments to the constructors can't be assigned a default value.

Steps to Reproduce

inductive Foo
| mk (x : Array Foo := #[])

Expected behavior: It should compile, and Foo.mk should have a default value for x.

Actual behavior: An error is thrown:

application type mismatch
  optParam _nested.Array_1 #[]
argument has type
  Array Foo
but function has type
  _nested.Array_1 → Type

Versions

Reproduced on

• 4.9.0-nightly-2024-05-25
• 4.11.0-nightly-2024-07-29

Impact

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[Kha]

duplicate of #4824