What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?

What is the difference between the remap, noremap, nno开发者_运维技巧remap and vnoremap mapping commands in Vim?

remap is an option that makes mappings work recursively. By default it is on and I'd recommend you leave it that way. The rest are mapping commands, described below:

:map and :noremap are recursive and non-recursive versions of the various mapping commands. For example, if we run:

:map j gg           (moves cursor to first line)
:map Q j            (moves cursor to first line)
:noremap W j        (moves cursor down one line)

Then:

• j will be mapped to gg.
• Q will also be mapped to gg, because j will be expanded for the recursive mapping.
• W will be mapped to j (and not to gg) because j will not be expanded for the non-recursive mapping.

Now remember that Vim is a modal editor. It has a normal mode, visual mode and other modes.

For each of these sets of mappings, there is a mapping that works in normal, visual, select and operator modes (:map and :noremap), one that works in normal mode (:nmap and :nnoremap), one in visual mode (:vmap and :vnoremap) and so on.

For more guidance on this, see:

:help :map
:help :noremap
:help recursive_mapping
:help :map-modes

I think the Vim documentation should've explained the meaning behind the naming of these commands. Just telling you what they do doesn't help you remember the names.

map is the "root" of all recursive mapping commands. The root form applies to "normal", "visual+select", and "operator-pending" modes. (I'm using the term "root" as in linguistics.)

noremap is the "root" of all non-recursive mapping commands. The root form applies to the same modes as map. (Think of the nore prefix to mean "non-recursive".)

(Note that there are also the ! modes like map! that apply to insert & command-line.)

See below for what "recursive" means in this context.

Prepending a mode letter like n modify the modes the mapping works in. It can choose a subset of the list of applicable modes (e.g. only "visual"), or choose other modes that map wouldn't apply to (e.g. "insert").

Use help map-modes will show you a few tables that explain how to control which modes the mapping applies to.

Mode letters:

• n: normal only
• v: visual and select
• o: operator-pending
• x: visual only
• s: select only
• i: insert
• c: command-line
• l: insert, command-line, regexp-search (and others. Collectively called "Lang-Arg" pseudo-mode)

"Recursive" means that the mapping is expanded to a result, then the result is expanded to another result, and so on.

The expansion stops when one of these is true:

1. the result is no longer mapped to anything else.
2. a non-recursive mapping has been applied (i.e. the "noremap" [or one of its ilk] is the final expansion).

At that point, Vim's default "meaning" of the final result is applied/executed.

"Non-recursive" means the mapping is only expanded once, and that result is applied/executed.

Example:

 nmap K H
 nnoremap H G
 nnoremap G gg

The above causes K to expand to H, then H to expand to G and stop. It stops because of the nnoremap, which expands and stops immediately. The meaning of G will be executed (i.e. "jump to last line"). At most one non-recursive mapping will ever be applied in an expansion chain (it would be the last expansion to happen).

The mapping of G to gg only applies if you press G, but not if you press K. This mapping doesn't affect pressing K regardless of whether G was mapped recursively or not, since it's line 2 that causes the expansion of K to stop, so line 3 wouldn't be used.

One difference is that:

• :map does nvo == normal + (visual + select) + operator pending
• :map! does ic == insert + command-line mode

as stated on help map-modes tables.

So: map does not map to all modes.

To map to all modes you need both :map and :map!.

I will explain mapping commands simply.

First, we have two general mapping commands:

• map - works recursively in normal, visual, select and operator pending modes.
• map! - works recursively in insert and command-line modes.

The non-recursive variations of these commands are:

• noremap - works non-recursively in normal, visual, select and operator pending modes.
• noremap! - works non-recursively in insert and command-line modes.

Then, we have mode-specific commands:

• nmap - works recursively in normal mode.
• imap - works recursively in insert mode.
• vmap - works recursively in visual and select modes.
• xmap - works recursively in visual mode.
• smap - works recursively in select mode.
• cmap - works recursively in command-line mode.
• omap - works recursively in operator pending mode.

And their non-recursive variations:

• nnoremap - works non-recursively in normal mode.
• inoremap - works non-recursively in insert mode.
• vnoremap - works non-recursively in visual and select modes.
• xnoremap - works non-recursively in visual mode.
• snoremap - works non-recursively in select mode.
• cnoremap - works non-recursively in command-line mode.
• onoremap - works non-recursively in operator pending mode.

Finally, remap is a boolean option that allows for mappings to work recursively. It is worth mentioning that you should always keep this option at the default on.