31.7 Maps for Repeated Edits

[Another way to do this is with @ -functions ( 31.4 ) . -JP]

Not every keymap is something you want to save in your .exrc file. Some maps are handy just because you have to do a repetitive series of edits. Developing a complex map to repeat your edits can save more time than it takes. For example, assume that you have a glossary with entries like this:

map - an ex command which allows you to associate 
a complex command sequence with a single key.

You want to convert this glossary list to nroff ( 43.13 ) format, so that it looks like:

.IP "map" 10n
An ex command which allows you to associate
a complex command sequence with a single key.

The best way to define a complex map is to do the edit once manually, writing down each keystroke that you must type. Then re-create these keystrokes as a map. You want to:

1. Insert the ms macro for an indented paragraph ( .IP ) at the beginning of the line. Insert the first quotation mark as well ( I.IP <"> ).

2. Press ESC to terminate text-input mode.

3. Move to the end of the first word ( e ) and add a second quotation mark, followed by a space and the size of the indent ( a<"> 10n ).

4. Press RETURN to insert a new line.

5. Press ESC to terminate text-input mode.

6. Remove the hyphen and two surrounding spaces ( 3x ) and capitalize the next word ( ~ ).

That's quite an editing chore if you have to repeat it more than a few times. With map you can save the entire sequence so that it can be re-executed with a single keystroke:

map g I.IP "^[ea" 10n^M^[3x~

(To set that option during a vi session, type a colon ( : ) first.) Note that you have to "quote" both the ESC and RETURN characters with CTRL-v ( 31.6 ) . ^[ is the sequence that appears when you type [CTRL-v] followed by [ESC] ^M is the sequence shown when you type [CTRL-v] [RETURN] .

Now, simply typing g will perform the entire series of edits. At a slow data rate you can actually see the edits happening individually. At a fast data rate it will seem to happen by magic.

Don't be discouraged if your first attempt at keymapping fails. A small error in defining the map can give very different results from the ones you expect. Type u to undo the edit, and try again.

[I like to write a keymap in a temporary file and edit it there until I get it right. For instance, I write my buffer and type :e temp.so to open the temporary file temp.so . I make the keymaps, one per line - without a colon ( : ) first. I write this map file ( :w ), then read it in to the editor ( :so  % ( 30.4 ) ). If I don't get an error, I switch to the original file ( :e  # ( 30.4 ) ) and try the map. Then I usually go back to the map file ( :e# ) again, fix the mistake :-) , and repeat the process until I get what I wanted. -JP  ]