To help you learn vi a little better, here are some 
	funky command sequences that will do powerful things
	in vi.

	1)	Piping your buffer thru a command

	  Let's say you want to quote something in a letter or
	  other text, by making it all upper-case.  
	  You could do this in vi command state:
	
		10!!tr 'a-z' 'A-Z'

	  Another example: let's say you needed to sort a
	  buffer alphabetically.  You could use this sequence
	  in vi to pipe the whole buffer to sort(1) and back again.

		1G!Gsort -df	
		

	2)	Pattern matching and replacement

	  The general pattern-match-and-replacement capabilities
	  of ex(1) are excellent.  They even provide interactive
	  query-replace.

	  Let's say you need replace the strings "XMACnnn' where 
	  'nnn' is a number, by 'ZMACROnnn' in almost every place
	  it occurs.  You could use this interactive replace to do
	  the job

		1,$s/XMAC\([0-9]*\)/ZMACRO\1/c

	  Each time vi finds a candidate for replacement, it will 
	  display the line on which was found and you can type
	  "yes" or "no" to replace or not replace.  For more info
	  on regular-expression pattern-matching and area addressing,
	  see "The Ex Reference Manual".


	3)	Macros  	(Yes, really!)

	  Vi has a limited macro facility that is part of ex(1).
	  The macros written using this facility can perform an
	  vi command, but have no parameters and do not nest.

	  Macros are defined using the ":map" command.  The basic
	  syntax is:
			:map lhs rhs

	  The lhs should be a single character (such as 'E' or '+')
	  and may be a control character if quoted with ^V.  Let's
	  define a macro to start up an nroff paragraph.  The command
	  character will be 'P'.

			:map P oi.pp^V^[o

	  You can learn more about macros in section 6.9 of
	  "An Introduction to Display Editing with Vi".


	4) 	Abbreviations

	  You can define abbreviations with the ex command 'ab'.
	  For instance, to define "ax" as an abbreviation for
	  "AIRX project", you would do this:

		:ab ax AIRX project

	  Abbreviations are different from macros in that they are
	  expanded in insert state, and they only work when the
	  lhs is a single word (i.e. if 'ax' were part of a longer
	  word it would be left alone).