Statement shouldn't inherit from Hashable
#203
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We made `Statement: Hashable` for convenience in holding onto statements in a shared key for SQLiteData, but that isn't really necessary, since we can always call out to the underlying query fragment to get a hashable value. This conformance unfortunately can cause bugs, including `==` resolving to the equality operator when a query operator was expected. Another bug is that `@Table @Selection` types conform to `Statement`, and this equatable implementation was preferred over the default synthesized version, making `Table` values equatable strictly by the underlying query, which meant `@Ephemeral` fields weren't taken into account at all. With 0.20.0, all `@Table` applications introduced a `Statement` conformance, and so this issue becomes much more widespread. While this change can break SQLiteData if someone upgrades StructuredQueries before upgrading SQLiteData with the changes from pointfreeco/sqlite-data#245.
mbrandonw
approved these changes
Oct 8, 2025
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We made
Statement: Hashablefor convenience in holding onto statements in a shared key for SQLiteData, but that isn't really necessary, since we can always call out to the underlying query fragment to get a hashable value.This conformance unfortunately can cause bugs, including
==resolving to the equality operator when a query operator was expected. Another bug is that@Table @Selectiontypes conform toStatement, and this equatable implementation was preferred over the default synthesized version, makingTablevalues equatable strictly by the underlying query, which meant@Ephemeralfields weren't taken into account at all.With 0.20.0, all
@Tableapplications introduced aStatementconformance, and so this issue becomes much more widespread.While this change can break SQLiteData if someone upgrades StructuredQueries before upgrading SQLiteData with the changes from pointfreeco/sqlite-data#245.