Function: c-looking-at-inexpr-block

c-looking-at-inexpr-block is a byte-compiled function defined in cc-engine.el.gz.

Signature

(c-looking-at-inexpr-block LIM CONTAINING-SEXP &optional CHECK-AT-END)

Documentation

This function has :around advice: csharp-looking-at-inexpr-block.

Source Code

;; Defined in /usr/src/emacs/lisp/progmodes/cc-engine.el.gz
(defun c-looking-at-inexpr-block (lim containing-sexp &optional check-at-end)
  ;; Return non-nil if we're looking at the beginning of a block
  ;; inside an expression.  The value returned is actually a cons of
  ;; either 'inlambda, 'inexpr-statement or 'inexpr-class and the
  ;; position of the beginning of the construct.
  ;;
  ;; LIM limits the backward search.  CONTAINING-SEXP is the start
  ;; position of the closest containing list.  If it's nil, the
  ;; containing paren isn't used to decide whether we're inside an
  ;; expression or not.  If both LIM and CONTAINING-SEXP are used, LIM
  ;; needs to be farther back.
  ;;
  ;; If CHECK-AT-END is non-nil then extra checks at the end of the
  ;; brace block might be done.  It should only be used when the
  ;; construct can be assumed to be complete, i.e. when the original
  ;; starting position was further down than that.
  ;;
  ;; This function might do hidden buffer changes.

  (save-excursion
    (let ((res 'maybe) (passed-bracket-pairs 0) bracket-pos passed-paren
	  haskell-op-pos
	  (closest-lim (or containing-sexp lim (point-min)))
	  ;; Look at the character after point only as a last resort
	  ;; when we can't disambiguate.
	  (block-follows (and (eq (char-after) ?{) (point))))

      ;; Search for a C++11 "->" which suggests a lambda declaration.
      (when (and (c-major-mode-is 'c++-mode)
		 (setq haskell-op-pos
		       (save-excursion
			 (while
			     (progn
			       (c-syntactic-skip-backward "^;=,}>" closest-lim t)
			       (and (eq (char-before) ?>)
				    (c-backward-token-2)
				    (not (looking-at c-haskell-op-re)))))
			 (and (looking-at c-haskell-op-re)
			      (point)))))
	(goto-char haskell-op-pos))

      (while (and (eq res 'maybe)
		  (progn (c-backward-syntactic-ws lim)
			 (> (point) closest-lim))
		  (not (bobp))
		  (progn (backward-char)
			 (looking-at "[]).]\\|\\w\\|\\s_"))
		  (c-safe (forward-char)
			  (goto-char (scan-sexps (point) -1))))

	(setq res
	      (if (looking-at c-keywords-regexp)
		  (let ((kw-sym (c-keyword-sym (match-string 1))))
		    (cond
		     ((and block-follows
			   (c-keyword-member kw-sym 'c-inexpr-class-kwds))
		      (and (not (eq passed-paren ?\[))
			   (or (not (looking-at c-class-key))
			       ;; If the class definition is at the start of
			       ;; a statement, we don't consider it an
			       ;; in-expression class.
			       (let ((prev (point)))
				 (while (and
					 (= (c-backward-token-2 1 nil closest-lim) 0)
					 (eq (char-syntax (char-after)) ?w))
				   (setq prev (point)))
				 (goto-char prev)
				 (not (c-at-statement-start-p)))
			       ;; Also, in Pike we treat it as an
			       ;; in-expression class if it's used in an
			       ;; object clone expression.
			       (save-excursion
				 (and check-at-end
				      (c-major-mode-is 'pike-mode)
				      (progn (goto-char block-follows)
					     (zerop (c-forward-token-2 1 t)))
				      (eq (char-after) ?\())))
			   (cons 'inexpr-class (point))))
		     ((c-keyword-member kw-sym 'c-paren-any-kwds) ; e.g. C++11 "throw" or "noexcept"
		      (setq passed-paren nil)
		      (setq passed-bracket-pairs 0)
		      (setq bracket-pos nil)
		      'maybe)
		     ((c-keyword-member kw-sym 'c-inexpr-block-kwds)
		      (when (not passed-paren)
			(cons 'inexpr-statement (point))))
		     ((c-keyword-member kw-sym 'c-lambda-kwds)
		      (when (or (not passed-paren)
				(eq passed-paren ?\())
			(cons 'inlambda (point))))
		     ((c-keyword-member kw-sym 'c-block-stmt-kwds)
		      nil)
		     (t
		      'maybe)))

		(if (looking-at "\\s(")
		    (if passed-paren
			(cond
			 ((and (eq passed-paren ?\[)
			       (eq (char-after) ?\[)
			       (not (eq (char-after (1+ (point))) ?\[))) ; C++ attribute.
			  ;; Accept several square bracket sexps for
			  ;; Java array initializations.
			  (setq passed-bracket-pairs (1+ passed-bracket-pairs))
			  'maybe)
			 ((and (eq passed-paren ?\()
			       (eq (char-after) ?\[)
			       (not (eq (char-after (1+ (point))) ?\[))
			       (eq passed-bracket-pairs 0))
			  ;; C++11 lambda function declaration
			  (setq passed-bracket-pairs 1)
			  (setq bracket-pos (point))
			  'maybe)
			 (t nil))
		      (when (not (looking-at "\\[\\["))
			(setq passed-paren (char-after))
			(when (eq passed-paren ?\[)
			  (setq passed-bracket-pairs 1)
			  (setq bracket-pos (point))))
		      'maybe)
		  'maybe))))

      (if (eq res 'maybe)
	  (cond
	   ((and (c-major-mode-is 'c++-mode)
		 block-follows
		 (eq passed-bracket-pairs 1)
		 (save-excursion
		   (goto-char bracket-pos)
		   (or (<= (point) (or lim (point-min)))
		       (progn
			 (c-backward-token-2 1 nil lim)
			 (and
			  (not (and (c-on-identifier)
				    (looking-at c-symbol-char-key)))
			  (not (looking-at c-opt-op-identifier-prefix)))))))
	    (cons 'inlambda bracket-pos))
	   ((and c-recognize-paren-inexpr-blocks
		 block-follows
		 containing-sexp
		 (eq (char-after containing-sexp) ?\())
	    (goto-char containing-sexp)
	    (if (or (save-excursion
		      (c-backward-syntactic-ws lim)
		      (while (and (eq (char-before) ?>)
				  (c-get-char-property (1- (point))
						       'syntax-table)
				  (c-go-list-backward nil lim))
			(c-backward-syntactic-ws lim))
		      (and (> (point) (or lim (point-min)))
			   (c-on-identifier)))
		    (and c-special-brace-lists
			 (c-looking-at-special-brace-list))
		    (and c-has-compound-literals
			 (save-excursion
			   (goto-char block-follows)
			   (not (c-looking-at-statement-block)))))
		nil
	      (cons 'inexpr-statement (point)))))

	res))))