repeat while end [repeat] |
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Syntax
Repeat while trueBoolean
(* code statements *)
end repeat
Description
repeat while keeps executing its enclosed script
code as long as the boolean expression following
while is true:
repeat while theTruth is true...end repeat
If the boolean expression that follows
while returns false, then the
repeat while loop is
terminated, and its enclosed script code will not execute anymore.
Script execution then resumes after the end repeat
part of the repeat while statement.
repeat while has the opposite effect of
repeat until; it keeps executing as long as some
boolean expression is true,
whereas repeat until keeps executing
until something is true. You
can also use exit within repeat
while to leave the loop. In general,
Repeat loops can contain nested
repeat loops, as well as other flow-control
statements such as if and tell.
Examples
This code shows how to use repeat while:
set theCount to 0
repeat while (theCount < 5)
set theCount to theCount + 1
log theCount
end repeat
The two code lines within this repeat while
statement block will continue executing (thus increasing the value of
theCount by one) while theCount
is less than 5. Each cycle through the loop tests the
boolean expression:
theCount < 5
and, as long as this expression returns true, the
enclosed code will execute again. The variable
theCount actually reaches 5 in the following code.
This is because it is eventually incremented to 4, then the:
repeat while (theCount < 5)
executes and, since theCount is still less than 5,
the enclosed script code executes once more, increasing the
variable's value to 5.
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