REBOL 3 Functions: loop

Description

The loop function is the simplest way to repeat the evaluation of a block. This function is very efficient and should be used if no loop counter is required.

loop 3 [print "hi"]
hi
hi
hi

Here's an example that creates a block of 10 random integers:

block: make block! 10
loop 10 [append block random 100]
probe block
[31 25 53 20 40 2 30 79 47 79]

Returned Value

When finished the loop function returns the final value the block:

num: 0
print loop 10 [num: num + 1]
10

Other Notes

• Negative or zero loop counts do not evaluate the block.
• If a decimal! count is used, it will be truncated to a lower integer value.
• The break function can be used to stop the loop at any time.
• The repeat function is similar to loop, except that it allows a variable to keep track of the current loop counter.