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[expr.sizeof]

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- ### Sizeof <a id="expr.sizeof">[[expr.sizeof]]</a>
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- The `sizeof` operator yields the number of bytes in the object
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- representation of its operand. The operand is either an expression,
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- which is an unevaluated operand (Clause  [[expr]]), or a parenthesized
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- *type-id*. The `sizeof` operator shall not be applied to an expression
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- that has function or incomplete type, to the parenthesized name of such
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- types, or to a glvalue that designates a bit-field. `sizeof(char)`,
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- `sizeof(signed char)` and `sizeof(unsigned char)` are `1`. The result of
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- `sizeof` applied to any other fundamental type ([[basic.fundamental]])
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- is *implementation-defined*.
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  [*Note 1*: In particular, `sizeof(bool)`, `sizeof(char16_t)`,
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  `sizeof(char32_t)`, and `sizeof(wchar_t)` are
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- implementation-defined.[^16] — *end note*]
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- [*Note 2*: See  [[intro.memory]] for the definition of *byte* and 
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- [[basic.types]] for the definition of *object
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- representation*. — *end note*]
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- When applied to a reference or a reference type, the result is the size
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- of the referenced type. When applied to a class, the result is the
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- number of bytes in an object of that class including any padding
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- required for placing objects of that type in an array. The size of a
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- most derived class shall be greater than zero ([[intro.object]]). The
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- result of applying `sizeof` to a base class subobject is the size of the
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- base class type.[^17] When applied to an array, the result is the total
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- number of bytes in the array. This implies that the size of an array of
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- *n* elements is *n* times the size of an element.
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- The `sizeof` operator can be applied to a pointer to a function, but
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- shall not be applied directly to a function.
 
 
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- The lvalue-to-rvalue ([[conv.lval]]), array-to-pointer (
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- [[conv.array]]), and function-to-pointer ([[conv.func]]) standard
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- conversions are not applied to the operand of `sizeof`. If the operand
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- is a prvalue, the temporary materialization conversion ([[conv.rval]])
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- is applied.
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-
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- The identifier in a `sizeof...` expression shall name a parameter pack.
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- The `sizeof...` operator yields the number of arguments provided for the
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- parameter pack *identifier*. A `sizeof...` expression is a pack
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- expansion ([[temp.variadic]]).
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  [*Example 1*:
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  ``` cpp
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  template<class... Types>
@@ -51,11 +46,12 @@ struct count {
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  };
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  ```
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  — *end example*]
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- The result of `sizeof` and `sizeof...` is a constant of type
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  `std::size_t`.
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- [*Note 3*: `std::size_t` is defined in the standard header
 
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  `<cstddef>` ([[cstddef.syn]], [[support.types.layout]]). — *end note*]
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+ #### Sizeof <a id="expr.sizeof">[[expr.sizeof]]</a>
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+ The `sizeof` operator yields the number of bytes occupied by a
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+ non-potentially-overlapping object of the type of its operand. The
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+ operand is either an expression, which is an unevaluated operand
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+ [[expr.prop]], or a parenthesized *type-id*. The `sizeof` operator shall
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+ not be applied to an expression that has function or incomplete type, to
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+ the parenthesized name of such types, or to a glvalue that designates a
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+ bit-field. The result of `sizeof` applied to any of the narrow character
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+ types is `1`. The result of `sizeof` applied to any other fundamental
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+ type [[basic.fundamental]] is *implementation-defined*.
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  [*Note 1*: In particular, `sizeof(bool)`, `sizeof(char16_t)`,
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  `sizeof(char32_t)`, and `sizeof(wchar_t)` are
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+ implementation-defined.[^21] — *end note*]
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+ [*Note 2*: See  [[intro.memory]] for the definition of byte and 
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+ [[basic.types]] for the definition of object
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+ representation. — *end note*]
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+ When applied to a reference type, the result is the size of the
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+ referenced type. When applied to a class, the result is the number of
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+ bytes in an object of that class including any padding required for
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+ placing objects of that type in an array. The result of applying
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+ `sizeof` to a potentially-overlapping subobject is the size of the type,
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+ not the size of the subobject. [^22] When applied to an array, the
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+ result is the total number of bytes in the array. This implies that the
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+ size of an array of n elements is n times the size of an element.
 
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+ The lvalue-to-rvalue [[conv.lval]], array-to-pointer [[conv.array]], and
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+ function-to-pointer [[conv.func]] standard conversions are not applied
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+ to the operand of `sizeof`. If the operand is a prvalue, the temporary
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+ materialization conversion [[conv.rval]] is applied.
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+ The identifier in a `sizeof...` expression shall name a pack. The
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+ `sizeof...` operator yields the number of elements in the pack
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+ [[temp.variadic]]. A `sizeof...` expression is a pack expansion
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+ [[temp.variadic]].
 
 
 
 
 
 
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  [*Example 1*:
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  ``` cpp
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  template<class... Types>
 
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  };
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  ```
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  — *end example*]
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+ The result of `sizeof` and `sizeof...` is a prvalue of type
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  `std::size_t`.
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+ [*Note 3*: A `sizeof` expression is an integral constant expression
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+ [[expr.const]]. The type `std::size_t` is defined in the standard header
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  `<cstddef>` ([[cstddef.syn]], [[support.types.layout]]). — *end note*]
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