Pass a variable to function with changing the variable (byRef)

1

hey guys
i want to solve this question (is a part of my function):


[COLOR=#808080]// root of my frame[/COLOR]
[COLOR=#0000ff]var [/COLOR]no = 0;
[COLOR=#800080]function [/COLOR]numberIncrease (num:[COLOR=#0000ff]Number[/COLOR])[INDENT]{[/INDENT]
[INDENT=2]num++;
[/INDENT]
[INDENT]}
[/INDENT]
[COLOR=#808080]// in a button[/COLOR]
[COLOR=#800080]on [/COLOR]([COLOR=#0000ff]release[/COLOR])[INDENT]{[/INDENT]
[INDENT=2]numberIncrease(no);
[/INDENT]
[INDENT]}

[/INDENT]

the question is why “no” remains unchanged and how to fix it without replacing “num++” with “no++”. thanks