signal

code: eval.c

DEFUN ("signal", Fsignal, Ssignal, 2, 2, 0,

doc: /* Signal an error. Args are ERROR-SYMBOL and associated DATA.

This function does not return.

An error symbol is a symbol wi≤th an `error-conditions' property

that is a list of condition names. The symbol should be non-nil.

A handler for any of those names will get to handle this signal.

The symbol `error' should normally be one of them.

DATA should be a list. Its elements are printed as part of the error message.

See Info anchor `(elisp)Definition of signal' for some details on how this

error message is constructed.

If the signal is handled, DATA is made available to the handler.

See also the function `condition-case'. */

attributes: noreturn)

(Lisp_Object error_symbol, Lisp_Object data)

{

/* If they call us with nonsensical arguments, produce "peculiar error". */

if (NILP (error_symbol) && NILP (data))

error_symbol = Qerror;

signal_or_quit (error_symbol, data, false);

eassume (false);

}

code: example.el

(signal 'dummy '("text"))

;; 両引数に nilを指定するとerrorになる

(signal nil nil)

;; 第1引数にnilで第2引数にシンボルのリストだとエラーにならない

(signal nil '(a))

(signal 'error '(a))