20.2.2 Code Characters for
The code character descriptions below contain a number of key words,
defined here as follows:
- Provide completion. <TAB>, <SPC>, and <RET> perform name
completion because the argument is read using
(see Completion). ? displays a list of possible completions.
- Require the name of an existing object. An invalid name is not
accepted; the commands to exit the minibuffer do not exit if the current
input is not valid.
- A default value of some sort is used if the user enters no text in the
minibuffer. The default depends on the code character.
- No I/O
- This code letter computes an argument without reading any input.
Therefore, it does not use a prompt string, and any prompt string you
supply is ignored.
Even though the code letter doesn't use a prompt string, you must follow
it with a newline if it is not the last code character in the string.
- A prompt immediately follows the code character. The prompt ends either
with the end of the string or with a newline.
- This code character is meaningful only at the beginning of the
interactive string, and it does not look for a prompt or a newline.
It is a single, isolated character.
Here are the code character descriptions for use with
- Signal an error if the current buffer is read-only. Special.
- Select the window mentioned in the first mouse event in the key
sequence that invoked this command. Special.
- If the command was invoked through shift-translation, set the mark and
activate the region temporarily, or extend an already active region,
before the command is run. If the command was invoked without
shift-translation, and the region is temporarily active, deactivate
the region before the command is run. Special.
- A function name (i.e., a symbol satisfying
- The name of an existing buffer. By default, uses the name of the
current buffer (see Buffers). Existing, Completion, Default,
- A buffer name. The buffer need not exist. By default, uses the name of
a recently used buffer other than the current buffer. Completion,
- A character. The cursor does not move into the echo area. Prompt.
- A command name (i.e., a symbol satisfying
- The position of point, as an integer (see Point). No I/O.
- A directory name. The default is the current default directory of the
default-directory (see File Name Expansion).
Existing, Completion, Default, Prompt.
- The first or next non-keyboard event in the key sequence that invoked
the command. More precisely, ‘e’ gets events that are lists, so
you can look at the data in the lists. See Input Events. No I/O.
You use ‘e’ for mouse events and for special system events
(see Misc Events). The event list that the command receives
depends on the event. See Input Events, which describes the forms
of the list for each event in the corresponding subsections.
You can use ‘e’ more than once in a single command's interactive
specification. If the key sequence that invoked the command has
n events that are lists, the nth ‘e’ provides the
nth such event. Events that are not lists, such as function keys
and ASCII characters, do not count where ‘e’ is concerned.
- A file name of an existing file (see File Names). The default
default-directory. Existing, Completion, Default,
- A file name. The file need not exist. Completion, Default, Prompt.
- A file name. The file need not exist. If the user enters just a
directory name, then the value is just that directory name, with no
file name within the directory added. Completion, Default, Prompt.
- An irrelevant argument. This code always supplies
the argument's value. No I/O.
- A key sequence (see Key Sequences). This keeps reading events
until a command (or undefined command) is found in the current key
maps. The key sequence argument is represented as a string or vector.
The cursor does not move into the echo area. Prompt.
If ‘k’ reads a key sequence that ends with a down-event, it also
reads and discards the following up-event. You can get access to that
up-event with the ‘U’ code character.
This kind of input is used by commands such as
- A key sequence, whose definition you intend to change. This works like
‘k’, except that it suppresses, for the last input event in the key
sequence, the conversions that are normally used (when necessary) to
convert an undefined key into a defined one.
- The position of the mark, as an integer. No I/O.
- Arbitrary text, read in the minibuffer using the current buffer's input
method, and returned as a string (see Input Methods). Prompt.
- A number, read with the minibuffer. If the input is not a number, the
user has to try again. ‘n’ never uses the prefix argument.
- The numeric prefix argument; but if there is no prefix argument, read
a number as with n. The value is always a number. See Prefix Command Arguments. Prompt.
- The numeric prefix argument. (Note that this ‘p’ is lower case.)
- The raw prefix argument. (Note that this ‘P’ is upper case.) No
- Point and the mark, as two numeric arguments, smallest first. This is
the only code letter that specifies two successive arguments rather than
one. This will signal an error if the mark is not set in the buffer
which is current when the command is invoked. No I/O.
- Arbitrary text, read in the minibuffer and returned as a string
(see Text from Minibuffer). Terminate the input with either
C-j or <RET>. (C-q may be used to include either of
these characters in the input.) Prompt.
- An interned symbol whose name is read in the minibuffer. Terminate
the input with either C-j or <RET>. Other characters that
normally terminate a symbol (e.g., whitespace, parentheses and
brackets) do not do so here. Prompt.
- A key sequence or
nil. Can be used after a ‘k’ or
‘K’ argument to get the up-event that was discarded (if any)
after ‘k’ or ‘K’ read a down-event. If no up-event has been
discarded, ‘U’ provides
nil as the argument. No I/O.
- A variable declared to be a user option (i.e., satisfying the
custom-variable-p). This reads the variable using
read-variable. See Definition of read-variable. Existing,
- A Lisp object, specified with its read syntax, terminated with a
C-j or <RET>. The object is not evaluated. See Object from Minibuffer. Prompt.
- A Lisp form's value. ‘X’ reads as ‘x’ does, then evaluates
the form so that its value becomes the argument for the command.
- A coding system name (a symbol). If the user enters null input, the
argument value is
nil. See Coding Systems. Completion,
- A coding system name (a symbol)—but only if this command has a prefix
argument. With no prefix argument, ‘Z’ provides
nil as the
argument value. Completion, Existing, Prompt.