Reset kj::Maybes with kj::none instead of {} - #2071
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The capnproto pull request capnproto/capnproto#2014 adds another assignment operator for Maybes. With a version of capnproto including that PR, we get compilation errors of the form: ``` external/workerd/src/workerd/io/worker.c++:2524:15: error: use of overloaded operator '=' is ambiguous (with operand types 'kj::Maybe<InspectorChannelImpl &>' and 'void') channel = {}; ~~~~~~~ ^ ~~ bazel-out/k8-dbg/bin/external/capnp-cpp/src/kj/_virtual_includes/kj/kj/common.h:1679:17: note: candidate function inline Maybe& operator=(decltype(nullptr)) { ptr = nullptr; return *this; } ^ bazel-out/k8-dbg/bin/external/capnp-cpp/src/kj/_virtual_includes/kj/kj/common.h:1682:17: note: candidate function inline Maybe& operator=(T* other) { ptr = other; return *this; } ^ ``` The Maybes that I fixed in this PR are all reference types (`Maybe<T&>`), so I’m not sure what assigning `{}` would do, since if it’s assigning a temporary, the reference will be garbage. However, in the three cases here, we seem to be resetting the objects, so assigning `kj::none` is correct.
jqmmes
approved these changes
Apr 30, 2024
harrishancock
approved these changes
Apr 30, 2024
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The capnproto pull request
capnproto/capnproto#2014 adds another assignment operator for Maybes. With a version of capnproto including that PR, we get compilation errors of the form:
The Maybes that I fixed in this PR are all reference types (
Maybe<T&>), so I’m not sure what assigning{}would do, since if it’s assigning a temporary, the reference will be garbage.However, in the three cases here, we seem to be resetting the objects, so assigning
kj::noneis correct.