While - Function Summary
While a condition block is TRUE, evaluates another block.
while cond-block body-block
cond-block - The cond-block argument. (must be: block)
body-block - The body-block argument. (must be: block)
The first block will be executed each time, and if it returns true the second block will be executed. Both blocks can include any number of expressions.
The most common mistake is to forget to provide a block for the first argument (the condition argument).
BREAK can be used to escape from the WHILE loop at any point.
for - Repeats a block over a range of values.