tmp/tmpjjboze40/{from.md → to.md}
RENAMED
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@@ -8,24 +8,10 @@ iteration-statement:
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do statement while '(' expression ')' ';'
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for '(' init-statement conditionₒₚₜ ';' expressionₒₚₜ ')' statement
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for '(' init-statementₒₚₜ for-range-declaration ':' for-range-initializer ')' statement
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```
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``` bnf
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for-range-declaration:
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attribute-specifier-seqₒₚₜ decl-specifier-seq declarator
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attribute-specifier-seqₒₚₜ decl-specifier-seq ref-qualifierₒₚₜ '[' identifier-list ']'
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```
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``` bnf
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for-range-initializer:
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expr-or-braced-init-list
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```
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See [[dcl.meaning]] for the optional *attribute-specifier-seq* in a
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*for-range-declaration*.
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[*Note 1*: An *init-statement* ends with a semicolon. — *end note*]
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The substatement in an *iteration-statement* implicitly defines a block
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scope [[basic.scope]] which is entered and exited each time through the
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loop. If the substatement in an *iteration-statement* is a single
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@@ -49,5 +35,31 @@ while (--x >= 0) {
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Thus after the `while` statement, `i` is no longer in scope.
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— *end example*]
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do statement while '(' expression ')' ';'
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for '(' init-statement conditionₒₚₜ ';' expressionₒₚₜ ')' statement
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for '(' init-statementₒₚₜ for-range-declaration ':' for-range-initializer ')' statement
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```
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[*Note 1*: An *init-statement* ends with a semicolon. — *end note*]
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The substatement in an *iteration-statement* implicitly defines a block
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scope [[basic.scope]] which is entered and exited each time through the
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loop. If the substatement in an *iteration-statement* is a single
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Thus after the `while` statement, `i` is no longer in scope.
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— *end example*]
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A *trivially empty iteration statement* is an iteration statement
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matching one of the following forms:
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- `while (` *expression* `) ;`
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- `while (` *expression* `) { }`
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- `do ; while (` *expression* `) ;`
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- `do { } while (` *expression* `) ;`
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- `for (` *init-statement* *expression*ₒₚₜ `; ) ;`
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- `for (` *init-statement* *expression*ₒₚₜ `; ) { }`
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The *controlling expression* of a trivially empty iteration statement is
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the *expression* of a `while`, `do`, or `for` statement (or `true`, if
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the `for` statement has no *expression*). A *trivial infinite loop* is a
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trivially empty iteration statement for which the converted controlling
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expression is a constant expression, when interpreted as a
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*constant-expression* [[expr.const]], and evaluates to `true`. The
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*statement* of a trivial infinite loop is replaced with a call to the
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function `std::this_thread::yield` [[thread.thread.this]]; it is
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*implementation-defined* whether this replacement occurs on freestanding
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implementations.
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[*Note 2*: In a freestanding environment, concurrent forward progress
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is not guaranteed; such systems therefore require explicit cooperation.
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A call to yield can add implicit cooperation where none is otherwise
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intended. — *end note*]
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