Remove always-on SingleUnderscorePattern language feature flag - #20222
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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Its only two consumers were the parser guards removed when the always-on SingleUnderscorePattern language feature was deleted, leaving the FSComp.txt entry and 13 xlf trans-units unreachable. Regenerated xlf via UpdateXlf. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
abonie
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…licts) Conflicts arose because main removed sibling always-on feature flags in the shared enum/strings; resolved to main's content minus this PR's own removal of SingleUnderscorePattern. Net change vs main is unchanged (feature removal only).
abonie
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Aug 12, 2026
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Fixes #20141
LanguageFeature.SingleUnderscorePatternhas been enabled for every accepted--langversionsince F# 4.7, so its flag was dead configuration. This collapses the guarded parser branches to their enabled behaviour;--disableLanguageFeature:SingleUnderscorePatternis no longer a recognised feature name.