Xcode – shortcut to make a block comment in Xcode

For those tasks I use most of the time block selection.

Put your cursor on the first # character, press CtrlV (or CtrlQ for gVim), and go down until the last commented line and press x, that will delete all the # characters vertically.

For commenting a block of text is almost the same:

1. First, go to the first line you want to comment, press CtrlV. This will put the editor in the VISUAL BLOCK mode.
2. Then using the arrow key and select until the last line
3. Now press ShiftI, which will put the editor in INSERT mode and then press #. This will add a hash to the first line.
4. Then press Esc (give it a second), and it will insert a # character on all other selected lines.

For the stripped-down version of vim shipped with debian/ubuntu by default, type : s/^/# in the third step instead (any remaining highlighting of the first character of each line can be removed with :nohl).

Here are two small screen recordings for visual reference.

Comment:

Uncomment:

YAML supports inline comments, but does not support block comments.

From Wikipedia:

Comments begin with the number sign ( # ), can start anywhere on a line, and continue until the end of the line

A comparison with JSON, also from Wikipedia:

The syntax differences are subtle and seldom arise in practice: JSON allows extended charactersets like UTF-32, YAML requires a space after separators like comma, equals, and colon while JSON does not, and some non-standard implementations of JSON extend the grammar to include Javascript's /* ... */ comments. Handling such edge cases may require light pre-processing of the JSON before parsing as in-line YAML.

# If you want to write
# a block-commented Haiku
# you'll need three pound signs