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+= Miscellaneous Syntax
+
+== +alias+
+
+The +alias+ keyword is most frequently used to alias methods. When aliasing a
+method you can use either its name or a symbol:
+
+ alias new_name old_name
+ alias :new_name :old_name
+
+For methods, Module#alias_method can often be used instead of +alias+.
+
+You can also use +alias+ to alias global variables:
+
+ $old = 0
+
+ alias $new $old
+
+ p $new # prints 0
+
+You may use +alias+ in any scope.
+
+== +undef+
+
+The +undef+ keyword prevents the current class from responding to calls to the
+named methods.
+
+ undef my_method
+
+You may use symbols instead of method names:
+
+ undef :my_method
+
+You may undef multiple methods:
+
+ undef method1, method2
+
+You may use +undef+ in any scope. See also Module#undef_method
+
+== +BEGIN+ and +END+
+
++BEGIN+ defines a block that is run before any other code in the current file.
+It is typically used in one-liners with <code>ruby -e</code>. Similarly +END+
+defines a block that is run after any other code.
+
++BEGIN+ must appear at top-level and +END+ will issue a warning when you use it
+inside a method.
+
+Here is an example:
+
+ BEGIN {
+ count = 0
+ }
+
+You must use <code>{</code> and <code>}</code> you may not use +do+ and +end+.
+
+Here is an example one-liner that adds numbers from standard input or any files
+in the argument list:
+
+ ruby -ne 'BEGIN { count = 0 }; END { puts count }; count += gets.to_i'
+