8. Macros

Buffers can also act as macros if they contain valid vi or ex commands.
To execute such a macro, type:

 
@a     - where "a" is the name of the buffer 

Example: From a file containing definitions of complex macros, yank
one paragraph (say, 20 lines) to a named buffer "a". Then
return to a file you were originally editing and type @a.
The commands contained in the buffer will be executed on the file
being edited.

It is possible to make files act as vi macros by using command:

 
:so filename 

The most powerful macros, however, are created using programs combined
into shell scripts (or DOS batch files), and acting as filters on the text
sent to them from within vi. Such shell scripts or programs must take standard
input and send results to standard output (which most UNIX tools do).

Even though seemingly strange at first, with a little practice using
vi becomes second nature.