[VIM] Back Reference

Replacement Part of :substitute

Replacement part of the S&R has its own special characters which we are going to use to fix grammar:

#	Meaning	#	Meaning
&	the whole matched pattern	\L	the following characters are made lowercase
\0	the whole matched pattern	\U	the following characters are made uppercase
\1	the matched pattern in the first pair of \(\)	\E	end of \U and \L
\2	the matched pattern in the second pair of \(\)	\e	end of \U and \L
...	...	\r	split line in two at this point
\9	the matched pattern in the ninth pair of \(\)	\l	next character made lowercase
~	the previous substitute string	\u	next character made uppercase

Now the full S&R to correct non-capital words at the beginning of the sentences looks like

s:\([.!?]\)\s\+\([a-z]\):\1  \u\2:g

We have corrected our grammar and as an extra job we replaced variable number of spaces between punctuation and the first letter of the next sentence with exactly two spaces.

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