I'm trying to write a replacement command that would search for a text containing at least 4 letters separated by spaces and remove the spaces:
%s/\v%(([a-zA-Z])\s){3,}([a-zA-Z])/\1\2/gc
But
L i g ht
becomes
ght
as expected because a group contains only the last match which was g
in that case. How to accumulate all the matches of group \1
and then join them?