Fix issue 23314 - Language spec falsely states that struct field inva… #3405
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…riants are checked This behavior has never been implemented, and users should not rely on it in their code.
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thewilsonator
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According to earlier versions of the language spec, checking the invariant of a struct would also cause its fields' invariants to be checked, recursively. SumType's invariant was added to make SumType behave consistently with other structs in this regard. The spec, however, was wrong: invariants of struct fields are not checked unless the field is accessed directly, and never have been. Thus, to make SumType behave consistently with other structs, its invariant must be removed. This change should not break any valid programs, since code that relies on the failure of an invariant has undefined behavior per the spec. Spec correction PR: dlang/dlang.org#3405
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According to earlier versions of the language spec, checking the invariant of a struct would also cause its fields' invariants to be checked, recursively. SumType's invariant was added to make SumType behave consistently with other structs in this regard. The spec, however, was wrong: invariants of struct fields are not checked unless the field is accessed directly, and never have been. Thus, to make SumType behave consistently with other structs, its invariant must be removed. This change should not break any valid programs, since code that relies on the failure of an invariant has undefined behavior per the spec. Spec correction PR: dlang/dlang.org#3405 Phobos PR: dlang/phobos#8558
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…riants are checked
This behavior has never been implemented, and users should not rely on
it in their code.