tmp/tmpg4xz9751/{from.md → to.md}
RENAMED
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### Assignment and compound assignment operators <a id="expr.ass">[[expr.ass]]</a>
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The assignment operator (`=`) and the compound assignment operators all
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group right-to-left. All require a modifiable lvalue as their left
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operand; their result is an lvalue
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In all cases, the assignment is
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operand. With respect to an
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-
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[*Note 1*: Therefore, a function call cannot intervene between the
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lvalue-to-rvalue conversion and the side effect associated with any
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single compound assignment operator. — *end note*]
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@@ -36,42 +37,44 @@ If the right operand is an expression, it is implicitly converted
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When the left operand of an assignment operator is a bit-field that
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cannot represent the value of the expression, the resulting value of the
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bit-field is *implementation-defined*.
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-
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-
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assignment is a discarded-value expression or an unevaluated operand
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The behavior of an expression of the form `E1 op= E2` is equivalent to
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`E1 = E1 op E2` except that `E1` is evaluated only once.
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[
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-
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-
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arithmetic type
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If the value being stored in an object is read via another object that
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overlaps in any way the storage of the first object, then the overlap
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shall be exact and the two objects shall have the same type, otherwise
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the behavior is undefined.
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[*Note
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left and right sides of the assignment operation; it is not a statement
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about how the target of the assignment
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[[basic.lval]]. — *end note*]
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A *braced-init-list* may appear on the right-hand side of
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- an assignment to a scalar, in which case the initializer list shall
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have at most a single element. The meaning of `x = {v}`, where `T` is
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the scalar type of the expression `x`, is that of `x = T{v}`. The
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meaning of `x = {}` is `x = T{}`.
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- an assignment to an object of class type, in which case the
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initializer list is passed as the argument to the assignment operator
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function selected by overload resolution
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[[over.match]]).
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[*Example 1*:
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``` cpp
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complex<double> z;
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### Assignment and compound assignment operators <a id="expr.ass">[[expr.ass]]</a>
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The assignment operator (`=`) and the compound assignment operators all
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group right-to-left. All require a modifiable lvalue as their left
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operand; their result is an lvalue of the type of the left operand,
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referring to the left operand. The result in all cases is a bit-field if
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the left operand is a bit-field. In all cases, the assignment is
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sequenced after the value computation of the right and left operands,
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and before the value computation of the assignment expression. The right
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operand is sequenced before the left operand. With respect to an
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indeterminately-sequenced function call, the operation of a compound
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assignment is a single evaluation.
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[*Note 1*: Therefore, a function call cannot intervene between the
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lvalue-to-rvalue conversion and the side effect associated with any
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single compound assignment operator. — *end note*]
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When the left operand of an assignment operator is a bit-field that
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cannot represent the value of the expression, the resulting value of the
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bit-field is *implementation-defined*.
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An assignment whose left operand is of a volatile-qualified type is
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deprecated [[depr.volatile.type]] unless the (possibly parenthesized)
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assignment is a discarded-value expression or an unevaluated operand
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[[term.unevaluated.operand]].
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The behavior of an expression of the form `E1 op= E2` is equivalent to
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`E1 = E1 op E2` except that `E1` is evaluated only once.
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[*Note 2*: The object designated by `E1` is accessed
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twice. — *end note*]
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For `+=` and `-=`, `E1` shall either have arithmetic type or be a
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pointer to a possibly cv-qualified completely-defined object type. In
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all other cases, `E1` shall have arithmetic type.
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If the value being stored in an object is read via another object that
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overlaps in any way the storage of the first object, then the overlap
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shall be exact and the two objects shall have the same type, otherwise
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the behavior is undefined.
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[*Note 3*: This restriction applies to the relationship between the
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left and right sides of the assignment operation; it is not a statement
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about how the target of the assignment can be aliased in general. See
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[[basic.lval]]. — *end note*]
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A *braced-init-list* may appear on the right-hand side of
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- an assignment to a scalar, in which case the initializer list shall
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have at most a single element. The meaning of `x = {v}`, where `T` is
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the scalar type of the expression `x`, is that of `x = T{v}`. The
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meaning of `x = {}` is `x = T{}`.
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- an assignment to an object of class type, in which case the
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initializer list is passed as the argument to the assignment operator
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function selected by overload resolution [[over.ass]], [[over.match]].
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[*Example 1*:
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``` cpp
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complex<double> z;
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