Character Class

Lua pattern classes like %a and %d match letters and digits.

character_class.lua

local code = 
local letter, digits = string.match(code, "(%a)(%d+)")

print("code=" .. code)
print("letter=" .. letter)
print("digits=" .. digits)

local code = 
local letter, digits = string.match(code, "(%a)(%d+)")

print("code=" .. code)
print("letter=" .. letter)
print("digits=" .. digits)

local code = 
local letter, digits = string.match(code, "(%a)(%d+)")

print("code=" .. code)
print("letter=" .. letter)
print("digits=" .. digits)

pattern classes `%a` matches a letter and `%d` matches a digit. A trailing `+` repeats the class one or more times.