Loops

A chunk of code can be repeated multiple times by using a loop. Lua provides three types of loop, the while, repeat, and for loops. Each loop type will be covered in depth, but the rest of the book will mainly use the for loop.

while loops

Syntactically, a while loop starts with the while keyword, followed by a Boolean condition and a do/end chunk. The loop will keep executing the chunk of code so long as the Boolean condition evaluates to true:

x = 10 -- Initialize a "control" variable

while x > 0 do -- Boolean condition: x > 0
    print ("hello, world")

    x = x - 1 -- Decrement the "control" variable
end

Infinite loops

One of the dangers of loops is an infinite loop. You get into an infinite loop when the condition of the loop never evaluates to false. Because the condition keeps being true, the loop goes on forever. The following code snippet demonstrates a simple infinite loop:

while true do
    print ("forever")
end

A more real-life example of an infinite loop would look like...