tmp/tmpmcpw_cfa/{from.md → to.md}
RENAMED
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The `switch` statement causes control to be transferred to one of
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several statements depending on the value of a condition.
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The condition shall be of integral type, enumeration type, or class
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type. If of class type, the condition is contextually implicitly
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converted
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-
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-
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-
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-
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``` bnf
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-
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```
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where the *constant-expression* shall be a converted constant
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There shall be at most one label of the form
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``` cpp
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default :
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@@ -29,34 +29,41 @@ default :
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within a `switch` statement.
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Switch statements can be nested; a `case` or `default` label is
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associated with the smallest switch enclosing it.
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When the `switch` statement is executed, its condition is evaluated
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to the
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`case` and `default` labels in themselves do not alter the flow of
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control, which continues unimpeded across such labels. To exit from a
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switch, see `break`,
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[*Note 1*: Usually, the substatement that is the subject of a switch is
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compound and `case` and `default` labels appear on the top-level
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statements contained within the (compound) substatement, but this is not
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required. Declarations can appear in the substatement of a `switch`
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statement. — *end note*]
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A `switch` statement of the form
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``` bnf
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-
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```
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is equivalent to
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except that names declared in the *init-statement* are in the same
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declarative region as those declared in the *condition*.
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The `switch` statement causes control to be transferred to one of
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several statements depending on the value of a condition.
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The condition shall be of integral type, enumeration type, or class
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type. If of class type, the condition is contextually implicitly
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converted [[conv]] to an integral or enumeration type. If the (possibly
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converted) type is subject to integral promotions [[conv.prom]], the
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condition is converted to the promoted type. Any statement within the
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`switch` statement can be labeled with one or more case labels as
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follows:
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``` bnf
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case constant-expression ':'
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```
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where the *constant-expression* shall be a converted constant expression
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[[expr.const]] of the adjusted type of the switch condition. No two of
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the case constants in the same switch shall have the same value after
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conversion.
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There shall be at most one label of the form
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``` cpp
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default :
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within a `switch` statement.
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Switch statements can be nested; a `case` or `default` label is
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associated with the smallest switch enclosing it.
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When the `switch` statement is executed, its condition is evaluated. If
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one of the case constants has the same value as the condition, control
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is passed to the statement following the matched case label. If no case
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constant matches the condition, and if there is a `default` label,
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control passes to the statement labeled by the default label. If no case
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matches and if there is no `default` then none of the statements in the
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switch is executed.
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`case` and `default` labels in themselves do not alter the flow of
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control, which continues unimpeded across such labels. To exit from a
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switch, see `break`, [[stmt.break]].
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[*Note 1*: Usually, the substatement that is the subject of a switch is
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compound and `case` and `default` labels appear on the top-level
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statements contained within the (compound) substatement, but this is not
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required. Declarations can appear in the substatement of a `switch`
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statement. — *end note*]
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A `switch` statement of the form
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``` bnf
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switch '(' init-statement condition ')' statement
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```
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is equivalent to
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``` bnf
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'{'
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init-statement
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switch '(' condition ')' statement
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'}'
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```
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except that names declared in the *init-statement* are in the same
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declarative region as those declared in the *condition*.
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