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Perl Programming/Keywords/while

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The while keyword

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while is the statement that uses the EXPRESSION, called the condition, to loop through a block until the condition is true. It is the opposite of the until statement.

Syntax

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  while EXPRESSION

Examples

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The code
$a = 5;
print $a++ while $a < 10;

prints the numbers 5 to 9 consecutively:

56789


The following two print statements
$i = 5;
print $i++ while $i <= 10;
$j = 5;
print $j++ until $j >  10;

return the same:

5678910
5678910


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