4.13. Lua process control

Lua programming language flow control statements are set by the program to set one or more conditional statements. When the condition is true executes the specified program code when the condition is false executes other specified code.

The following is a typical flow chart of process control:

The conditional expression result of the control structure can be any value Lua believes that false and nil are false, true and non nil is true.

It should be noted that 0 in Lua is true :

4.13.1. Example #

--[ 0 is true ]
if(0)
then
    print("0 is true")
end

The output of the above code is:

0 is true

Lua provides the following control structure statements:

Statement	Description
If statement	If statement? It consists of a Boolean expression as a conditional judgment,followed by other statements.
If…else statement	If statement? Can you communicate with? Use else statement in combination, Execute the else statement code when the if conditional expression is false.
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