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@cpp class | null tested for truth with a boolean (h && cond): no instanceof - #765
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…nger asks instanceof `h && n == 3` with h a `Handle | null` (@cpp) is a union of the class, null and boolean; castFromUnion's ___cast helper tested each class member with instanceof, which a @cpp class refuses (its objects carry no type info). When the class need not be told apart - the only class of the union, or the union tested for truth - typeof has narrowed t enough: `return t`. Otherwise only the non-@cpp classes are tested. TSLANG_ISSUES 23. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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* TSLANG_ISSUES: 22, one-field @value T | null crash; 23, h && cond with a @cpp class | null Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * TSLANG_ISSUES: 22 and 23 fixed (#763, #765) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
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Fixes TSLANG_ISSUES 23:
if (h && n == 3)withha@cppclass| nullfailed with "instanceof can't be used with a @cpp class" and "'___cast' not all generic types can be identified".h && n == 3is typedHandle | null | boolean; making it a boolean goes throughcastFromUnion, whose generated___casttests every class member withinstanceof, which a@cppclass refuses (its objects are C++ objects with no type information).writeClassTestslambda (used by the null-target and default branches).@cppclass and the class need not be told apart (the only class of the union, or tested for truth), it emitsreturn t;:typeofhas narrowedtenough, and truthiness is the null test.instanceofis emitted only for the non-@cppclasses.Test:
tests/00cpp_union_truth.ts(hand-made C++ object):h && n == 3,enabled && hwith a handle and null, and two@cppclasses in a union with a boolean tested for truth. Registered compile/JIT default + own, and in the rc/none corpus. Full release ctest passes.Issue 22 (one-field
@valueT | null) was already fixed by #763; checked with the current build.🤖 Generated with Claude Code