function return parameters modified

Getting Started Newbie Questions
#1

How i can modified the parameters in a function

in c++  

functionName( double & data )

in Corona sdk?

#2

Question is a bit wrong, it should be: in Lua? Corona sdk is framework but programming language is Lua. So if you have something language specific then usually search often Lua forums

But to point. In Lua all variables are passed by value. You cannot make variable to be passed by reference.
However, value of string, table, userdata is it’s memory address which is reference.

So summing up:
you cannot chose what to pass by reference and what by value. Lua has this set in stone what is passsed in which way. Tables, strings and userdata are passed always by reference and other types are always passed by value.

#3

Thanks. I got it.

#4

Question is a bit wrong, it should be: in Lua? Corona sdk is framework but programming language is Lua. So if you have something language specific then usually search often Lua forums

But to point. In Lua all variables are passed by value. You cannot make variable to be passed by reference.
However, value of string, table, userdata is it’s memory address which is reference.

So summing up:
you cannot chose what to pass by reference and what by value. Lua has this set in stone what is passsed in which way. Tables, strings and userdata are passed always by reference and other types are always passed by value.

#5

Thanks. I got it.