Regex to change the number of spaces in an indent level

Question

Let\'s say you have some lines that look like this

1  int some_function() {
2    int x = 3;  // Some silly comment

And so on. The indentation i

Answer 1

You can try this:

^(\s{2})|((?<=\n(\s)+))(\s{2})

Breakdown:

^(\s{2})  = Searches for two spaces at the beginning of the line
((?<=\n(\s)+))(\s{2}) = Searches for two spaces
    but only if a new line followed by any number of spaces is in front of it.
    (This prevents two spaces within the line being replaced)

I'm not completely familiar with perl, but I would try this to see if it work:

s/^(\s{2})|((?<=\n(\s)+))(\s{2})/\s\s\s/g

As @Jan pointed out, there can be other non-space whitespace characters. If that is an issue, try this:

s/^( {2})|((?<=\n( )+))( {2})/   /g