fix: re-privatize constant name prefix in realizeConst to avoid diamond import collisions#12964
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fix: re-privatize constant name prefix in realizeConst to avoid diamond import collisions#12964
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Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…mond import collisions When `realizeConst` generates auxiliary declarations (like `_sparseCasesOn`) for a private constant from an imported module, the name prefix inherited the original module's private prefix. Since the name was already private, `mkUniqueName` would not re-privatize it under the current module, causing two importing modules to generate identically-named auxiliary declarations. This led to "environment already contains" errors when both modules were imported together (diamond import pattern). The fix re-privatizes the constant name under the current module before passing it to `withDeclNameForAuxNaming`, so each realizing module generates distinctly-named auxiliary declarations. Fixes #12825 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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This PR fixes an issue where
realizeConstwould generate auxiliary declarations(like
_sparseCasesOn) using the original defining module's private name prefixrather than the realizing module's prefix. When two modules independently realized
the same imported constant, they produced identically-named auxiliary declarations,
causing "environment already contains" errors on diamond import.
The fix re-privatizes the constant name under the current module before passing it
to
withDeclNameForAuxNaming, ensuring each realizing module generates distinctlynamed auxiliary declarations.
Fixes #12825
Co-Authored-By: Claude Opus 4.6 noreply@anthropic.com