Scope modifiers: Difference between revisions
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return /*compliments to Jules Verne's Captain Nemo? */</lang>
=={{header|Ruby}}==
===Variables===
The scope of a variable is decided by its first character(s).
$variable : global variable. Visible everywhere. Very seldom used.<br>
@@variable: class variable. Visible inside a class and it's instances. Very seldom used<br>
@variable : instance variable. Visible inside a class instance. Commonly used.<br>
variable : local variable. visible inside whichever comes first: a loop, a proc, a method, a class, a program.
===Methods===
Instance methods may be public, private or protected<br>
A public method is visible and usable inside and outside an instance.<br>
A private method is internal to the class, and it can only be invoked from within the class (or subclass).<br>
A protected method is available within a class and available to instances of the same class.<br>
By default, methods are public. Use like this:
<lang ruby>
<pre>
class Demo
#public methods here
protected
#protect methods here
private
#private methods
end
</pre>
</lang>
Ruby is an open language. Declaring methods private prevents inadvertend use of methods not meant to be used outside a class. However it is easy to circumvent with metaprogramming methods like instance_eval.
=={{header|Tcl}}==
===Variables===
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