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Simple Vim Macros

Uncle Jubba — Wed, 18 Nov 2009 18:27:29 +0000

I found myself editing a configuration file (multiple actually) at work today and ran into an issue. The config file looked similar to:

Var_1=A
Var_2=B
Var_3=C
...
Var_146=ABC
Var_147=ABD

As it happened I needed to remove one of the lines at position 23. The program that reads/uses these config files has an issue if there is a break in the sequence. So after removing the line with “Var_23″ I needed to shift all of the numbers in following lines down by 1. Here is how I accomplished that.

In vim I put my cursor on the 24 in the line that now follows the “Var_22″ line and performed the following commands:

qa
CTRL-X
j
q
125@a

Here is what happened broken down by line:

1: Here I am recording a macro (q) with the name or identifier of ‘a’. Note you will probably see some indication in the last line that you are in “recording” mode.

2: CTRL-X decrements the number under the cursor. Since I am on the 24 that decrements it to 23.

3: I move down 1 line and now the cursor is on the 25 in the next line.

4: I quit recording the macro. I know have a named (a) macro that includes the commands “decrement the number under the cursor and move down one row”.

5: I perform that named (a) macro 125 times. Now realistically I only needed to do it 123 times. It didn’t seem to matter that I used 125 but YMMV. The first line after the last line I wanted to change was a blank line so I assume the macro quit when the CTRL-X failed. You are probably better off using the exact number.

And there you have it. I successfully renumbered all of the variables below the line I deleted to be in sequence.

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Add A Comma To The End Of A Line

Uncle Jubba — Fri, 23 Jan 2009 16:59:49 +0000

I work with long lists and WinSQL a lot. I always find myself wishing these long lists had commas at the end for pasting into a SQL where clause using “IN” for the list. This can be accomplished in one of two ways.

From the command line:

sed "s/$/,/g"

I usually pipe the output there to a new file.

In vi (from command mode):

:%s/$/,/g

The “%” says to perfom the substitution on the whole file. In both cases we are doing a substitution of “$” (the end of the line) with a “,”.

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Global Search And Replace In Vi

Uncle Jubba — Mon, 08 Dec 2008 18:30:40 +0000

To perform a global search and replace in vi do:

:%s/search_string/replacement_string/g

If you want to confirm each replacement add a “c” after the “g” at the end of the string.

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