[stmt.iter.general] (original) (raw)

8 Statements [stmt.stmt]

8.6 Iteration statements [stmt.iter]

8.6.1 General [stmt.iter.general]

Iteration statements specify looping.

The substatement in an iteration-statement implicitly defines a block scope which is entered and exited each time through the loop.

If the substatement in an iteration-statement is a single statement and not a compound-statement, it is as if it was rewritten to be a compound-statement containing the original statement.

[Example 1:

while (--x >= 0) int i;can be equivalently rewritten aswhile (--x >= 0) { int i;}

Thus after the while statement, i is no longer in scope.

— _end example_]

If a name introduced in aninit-statement or for-range-declarationis redeclared in the outermost block of the substatement, the program is ill-formed.

[Example 2: void f() { for (int i = 0; i < 10; ++i) int i = 0; for (int i : { 1, 2, 3 }) int i = 1; } — _end example_]