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SYNTAX
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SYNTAX
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The while loop statement:
while (cond_expr) {
statements;
}
Wading In Deeper
The while loop repeatedly executes the block of code indicated by statements as long as the
conditional expression, cond_expr, is true (nonzero). The state of the loop must be initialized
prior to the while statement, and modification of the state must be explicit in the block of
code. When the conditional expression, cond_expr, evaluates to false the loop terminates.
The do-while Loop
The do-while loop is nearly identical to the while loop. The distinction between the two is
important, though. As you can see from Listing 2.2, the while loop checks the conditional
expression at the top of the loop. In the case of the do-while loop, the conditional expression
is checked at the bottom of the loop:
bool done = false;
do {
// some code
done = SomeFunctionReturningABool();
// more code
} while (!done)
Whether you use a while or a do-while loop depends on what the loop itself does.
The do-while loop statement:
do {
statements;
} while (cond_expr)
The do loop repeatedly executes the block of code indicated by statements as long as the
conditional expression, cond_expr, is true (nonzero). The state of the loop must be initialized
prior to the do statement, and modification of the state must be explicit in the block of code.
When the conditional expression, cond_expr, evaluates to false, the loop terminates.
goto
I’ll mention goto just so you know it exists. The goto statement allows you to jump program
execution to a label that you have previously declared by using a term followed by a colon.
The following code snippet illustrates this:
bool done = false;
startPoint:
// do some stuff
if (!done) goto(startPoint);
// loop over, moving on...
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