Thanks for answer, sorry for stupid questions but I am not so experienced in programming at all.
So what exactly it means length {chars "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"} - that is declaration what kind of characters can be used for generating random number?
What confuses me in above what is purpose of using length? So how 10 in call library::randomNumberGenerator 10 is passed and used by proc? I assumed that 10 passed to proc is defining how long random string should be?
Or I am just confused by length - it's not function but var that is used to receive 10 when call is performed?
Piotr