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Open Source Technologies

Notes break;

case ‘n’:
case ‘N’:

print “The answer was no\n”;
break;

default:
print “Error: $answer is not a valid answer\n”;

break;
}
It is important to include a break statement at the end of any code that will
be executed as part of a case statement. Without a break statement, the
program flow will continue to the next case statement and ultimately to the
default statement. In most cases, this will result in unexpected behavior,
likely incorrect!

6.1.7 Loop Control Structures

Loop control structures are used for repeating certain tasks in your program, such as iterating
over a database query result set.
6.1.7.1 While Loops
Statement Statement List

while (expr) statement while (expr) :statement list endwhile;

while loops are the simplest kind of loops. In the beginning of each iteration, the while’s truth
expression is evaluated. If it evaluates to true, the loop keeps on running and the statements
inside it are executed. If it evaluates to false, the loop ends and the statement(s) inside the loop
is skipped. For example, here’s one possible implementation of factorial, using a while loop
(assuming $n contains the number for which we want to calculate the factorial):
$result = 1;

while ($n > 0) {
$result *= $n—;

}
print “The result is $result”;

Loop Control: break and continue
break;

break expr;
continue;

continue expr;

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