Control structures

Control structures are used to make decisions in code; they control the path of code based on a Boolean value. Lua provides the if statement for this purpose. An if statement is followed by a Boolean condition, which in turn is followed by a then/end chunk. The chunk is only executed when the Boolean condition evaluates to true.

The most basic syntax of an if statement is as follows:

if

A logical control structure always starts with an if statement. As described previously, an if statement consists of the if keyword, a Boolean expression, and a then/end chunk. The then/end chunk is only executed when the Boolean condition evaluates to true. The following code sample demonstrates the basic use of an if statement:

print ("Enter your name")
name = io.read()

if #name <= 3 then
    print ("that's a short name, " .. name)
end

elseif

You might want to make a more complicated decision than a simple if statement allows. For example, you may want to do one thing if the length of a...