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Created: March 14, 2001 Complexity: basic Author: Anon Minimum version: 5.7 Karma: 102/51 Imported from: Tip#49

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You can change the case of text:

Toggle case "HellO" to "hELLo" with g~ then a movement.

Uppercase "HellO" to "HELLO" with gU then a movement.

Lowercase "HellO" to "hello" with gu then a movement.

Alternatively, you can visually select text then press ~ to toggle case, or U to convert to uppercase, or u to convert to lowercase.

Contents 1 Examples 2 Title case 3 Twiddle case 4 References 5 Comments

[edit] Examples

~

Toggle case of the character under the cursor, or all visually-selected characters.

3~

Toggle case of the next three characters.

g~3w

Toggle case of the next three words.

g~iw

Toggle case of the current word (inner word – cursor anywhere in word).

g~$

Toggle case of all characters to end of line.

g~~

Toggle case of the current line (same as V~).

The above uses ~ to toggle case. In each example, you can replace ~ with u to convert to lowercase, or with U to convert to uppercase. For example:

U

Uppercase the visually-selected text.

First press v or V then move to select text.

If you don't select text, pressing U will undo all changes to the current line.

gUU

Change the current line to uppercase (same as VU).

gUiw

Change current word to uppercase.

u

Lowercase the visually-selected text.

If you don't select text, pressing u will undo the last change.

guu

Change the current line to lowercase (same as Vu).

[edit] Title case

The :s substitute command can change case (see :help s/\u).

The following converts the current line to Title Case (all lowercase, except for initial uppercase letters):

:s/\<\(\w\)\(\w*\)\>/\u\1\L\2/g

Explanation The search pattern is \<\(\w\)\(\w*\)\> which searches for \< (beginning of word), then \w (a word character), then \w* (zero or more word characters), then \> (end of word). The \(...\) create subexpressions to be recalled with \1 and \2 in the replacement. The replacement is \u\1\L\2 which substitutes the two subexpressions transformed: The \u converts the first character of what follows to uppercase, while \L converts all of what follows to lowercase.

[edit] Twiddle case

With the following (for example, in vimrc), you can visually select text then press ~ to convert the text to UPPER CASE, then to lower case, then to Title Case. Keep pressing ~ until you get the case you want.

function! TwiddleCase(str)
  if a:str ==# toupper(a:str)
    let result = tolower(a:str)
  elseif a:str ==# tolower(a:str)
    let result = substitute(a:str,'\(\<\w\+\>\)', '\u\1', 'g')
  else
    let result = toupper(a:str)
  endif
  return result
endfunction
vnoremap ~ ygv"=TwiddleCase(@")<CR>Pgv

[edit] References

• :help case

[edit] Comments

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