57 lines
1.1 KiB
ReStructuredText
57 lines
1.1 KiB
ReStructuredText
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.. title:: clang-tidy - google-explicit-constructor
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google-explicit-constructor
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===========================
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Checks that constructors callable with a single argument and conversion
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operators are marked explicit to avoid the risk of unintentional implicit
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conversions.
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Consider this example:
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.. code-block:: c++
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struct S {
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int x;
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operator bool() const { return true; }
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};
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bool f() {
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S a{1};
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S b{2};
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return a == b;
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}
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The function will return ``true``, since the objects are implicitly converted to
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``bool`` before comparison, which is unlikely to be the intent.
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The check will suggest inserting ``explicit`` before the constructor or
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conversion operator declaration. However, copy and move constructors should not
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be explicit, as well as constructors taking a single ``initializer_list``
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argument.
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This code:
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.. code-block:: c++
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struct S {
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S(int a);
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explicit S(const S&);
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operator bool() const;
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...
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will become
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.. code-block:: c++
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struct S {
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explicit S(int a);
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S(const S&);
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explicit operator bool() const;
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...
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See https://google.github.io/styleguide/cppguide.html#Explicit_Constructors
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