for
Synopsis:
for ([<pre>],[<condition>
Description:
for is a general purpose
loop. It is modeled on the C for statement, and works in a very similar manner.
Aside from the action, there are three parts to a for loop:
* The "pre" part is executed before the loop begins iterating. This is often
used for initializing counters and other variables that will be used in the
loop.
* Before each loop iteration, the "condition" is checked. Most often, this is
used to see if the counter has exceeded a certain limit. The condition may contain
any expression legal in the if command. Because of this, the loop does
not necessarily have to iterate at all.
* The "post" part is executed after the condition, if the condition returns
true. This is generally used to increment a counter that gets checked by the
condition statement.
Multiple commands may be used in each part; they must be separated by semicolons (giving it something of a reverse-C syntax). Note that there does not necessarily need to be any commands in any part. The action is optional as well.
Examples:
To display a warning message 3 times:
for (@ xx = 3, xx > 0, @ xx--)
{
..echo WARNING! This ship will self destruct in $xx seconds!
}
A infinite loop that behaves like
the Unix 'yes' command:
for ( ,, ) {
..echo yes
}
See Also:
fe,
fec
foreach
while, until