tmp/tmp00tsx85r/{from.md → to.md}
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## Local class declarations <a id="class.local">[[class.local]]</a>
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A class can be declared within a function definition; such a class is
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called a *local
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enclosing scope. The local class is in the scope of the enclosing scope,
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and has the same access to names outside the function as does the
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enclosing function.
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[*Example 1*:
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``` cpp
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int x;
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void f() {
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static int s;
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int x;
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const int N = 5;
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extern int q();
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struct local {
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int g() { return x; } // error: odr-use of
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int h() { return s; } // OK
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int k() { return ::x; } // OK
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int l() { return q(); } // OK
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int m() { return N; } // OK: not an odr-use
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int* n() { return &N; } // error: odr-use of
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};
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}
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local* p = 0; // error: local not in scope
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```
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— *end example*]
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An enclosing function has no special access to members of the local
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class; it obeys the usual access rules
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definition, if they are defined at all.
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If class `X` is a local class a nested class `Y` may be declared in
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class `X` and later defined in the definition of class `X` or be later
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defined in the same scope as the definition of class `X`. A class nested
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within a local class is a local class.
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A local class
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## Local class declarations <a id="class.local">[[class.local]]</a>
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A class can be declared within a function definition; such a class is
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called a *local class*. The name of a local class is local to its
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enclosing scope. The local class is in the scope of the enclosing scope,
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and has the same access to names outside the function as does the
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enclosing function.
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[*Note 1*: A declaration in a local class cannot odr-use
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[[basic.def.odr]] a local entity from an enclosing scope. — *end note*]
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[*Example 1*:
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``` cpp
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int x;
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void f() {
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static int s;
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int x;
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const int N = 5;
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extern int q();
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int arr[2];
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auto [y, z] = arr;
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struct local {
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int g() { return x; } // error: odr-use of non-odr-usable variable x
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int h() { return s; } // OK
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int k() { return ::x; } // OK
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int l() { return q(); } // OK
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int m() { return N; } // OK: not an odr-use
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int* n() { return &N; } // error: odr-use of non-odr-usable variable N
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int p() { return y; } // error: odr-use of non-odr-usable structured binding y
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};
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}
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local* p = 0; // error: local not in scope
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```
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— *end example*]
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An enclosing function has no special access to members of the local
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class; it obeys the usual access rules [[class.access]]. Member
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functions of a local class shall be defined within their class
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definition, if they are defined at all.
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If class `X` is a local class a nested class `Y` may be declared in
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class `X` and later defined in the definition of class `X` or be later
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defined in the same scope as the definition of class `X`. A class nested
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within a local class is a local class.
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[*Note 2*: A local class cannot have static data members
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[[class.static.data]]. — *end note*]
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