vim - How to insert spaces up to column X to line up things in columns?

Question

I have my source code for copy operators written as follows.

foo = rhs.foo;
foobar = rhs.foobar;
bar = rhs.bar;
toto = rhs.toto;

I'd like to line things up as follows (more human readable, isn't it?).

foo    = rhs.foo;
foobar = rhs.foobar;
bar    = rhs.bar;
toto   = rhs.toto;

Is there a VIM magic insert-up-to-column-N, or something like that that would allow me to line things up using a couple of keystrokes per line?

Answer 1

The other answers here are great, especially @nelstrom's comment for Tabular.vim and his excellent screencast.

But if I were feeling too lazy to install any Vim plugins, yet somehow willing to use Vim macros, I'd use macros.

The algorithm:

For each line,
    Add tons of spaces before the symbol =
    Go to the column you want to align to
    Delete all text up to =, thereby shifting the = into the spot you want.

For your example,

foo = rhs.foo;
foobar = rhs.foobar;
bar = rhs.bar;
toto = rhs.toto;

Position the cursor anywhere on the first line and record the macro for that line by typing, in normal mode:

qa0f=100i <Esc>8|dwjq

Which translates to:

1. qa -- Record a macro in hotkey a
2. 0 -- Go to the beginning of the line
3. f= -- Go to the first equals sign
4. 100i <Esc> -- (There's a single space after the i, and the <Esc> means press escape, don't type "<Esc>".) Insert 100 spaces
5. 8| -- Go to the 8th column (sorry, you'll have to manually figure out which column to align to)
6. dw -- Delete until the next non-space character
7. j -- Go to the next line
8. q -- Stop recording.

Then run the macro stored at hotkey a, 3 times (for the 3 remaining lines), by putting the cursor on the second line and pressing:

3@a