[stmt.while]

# 8 Statements [[stmt]](./#stmt)

## 8.6 Iteration statements [[stmt.iter]](stmt.iter#stmt.while)

### 8.6.2 The while statement [stmt.while]

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/statements.tex#L607)

In the while statement, the substatement is executed repeatedly
until the value of the condition ([[stmt.pre]](stmt.pre "8.1 Preamble")) becomesfalse[.](#1.sentence-1)

The test takes place before each execution of the
substatement[.](#1.sentence-2)

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/statements.tex#L613)

A while statement is equivalent to

*label* :  
{  
 if ( [*condition*](stmt.pre#nt:condition "8.1 Preamble [stmt.pre]") ) {  
 [*statement*](stmt.pre#nt:statement "8.1 Preamble [stmt.pre]")  
 goto *label* ;  
 }  
}

[*Note [1](#note-1)*:

The variable created in the condition is destroyed and created with each
iteration of the loop[.](#2.sentence-1)

[*Example [1](#example-1)*: struct A {int val;
 A(int i) : val(i) { }~A() { }operator bool() { return val != 0; }};int i = 1;while (A a = i) {// ... i = 0;}

In the while-loop, the constructor and destructor are each called twice,
once for the condition that succeeds and once for the condition that
fails[.](#2.sentence-2)

— *end example*]

— *end note*]