`FromJson Name` does not round-trip hygienic names
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bug
P-low
- Dominant language
- Lean
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Description
import Lean
open Lean
#eval (fromJson? (toJson (addMacroScope `Module `foo 42)) : Except _ Name)
-- Except.error "expected a `Name`, got '\"foo._@.Module._hyg.42\"'"
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Research direction
Start with the Lean snippet in the issue and reproduce the failing toJson/fromJson? round trip for addMacroScope names. Trace the Name JSON encoding and decoding paths, then verify that the hygienic name no longer produces the shown Except.error.
Written by the indexing model from the issue text.
Assessment
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100