How to regex in Vim

Question

I want to add some text before each return For example we have :

void* foo (){
   if (something){ 
   return A;
   }
do_something;
// That return word may be ignored, because it's comment
do_something;
returns(); //It may ignored to
return ;
}

I need :

void* foo (){
   if (something){
   END;
   return A;
   }
do_something;
// That return word may be ignored, becouse it's comment
do_something;
returns(); //It may ignored to
END;
return ;
}

I can't build regex for search request. It may looks like "

return"< some text here started with space symbol, or nothing >;<endline>

How I can make it in VIM?

Answer 1

Using hold registers is an easy way to do this:

%s/^\(\s*\)\(return\>.*\)/\1END;\r\1\2/g

The meanings:

%s - global substitute
/  - field separator
^  - start of line
\( - start hold pattern
\s - match whitespace
*  - 0 or more times
\) - end hold pattern
\> - end of word boundary (prevent returns matching return)
.  - match any character
\1 - recall hold pattern number 1
\2 - recall hold pattern number 2
\r - <CR>
g  - Replace all occurrences in the line

Answer 2

You may use the global command as follows:

:g/^\s*return\>/normal OEND;

It searches for lines having any number of whitespace and the word return, executes the command O and adds the "END;"

Bonus feature the END; is 'auto indented'.