Function: define-lex-block-analyzer

define-lex-block-analyzer is a macro defined in lex.el.gz.

Signature

(define-lex-block-analyzer NAME DOC SPEC1 &rest SPECS)

Documentation

Create a lexical analyzer NAME for paired delimiters blocks.

It detects a paired delimiters block or the corresponding open or close delimiter depending on the value of the variable semantic-lex-current-depth. DOC is the documentation string of the lexical analyzer. SPEC1 and SPECS specify the token symbols and open, close delimiters used. Each SPEC has the form:

(BLOCK-SYM (OPEN-DELIM OPEN-SYM) (CLOSE-DELIM CLOSE-SYM))

where BLOCK-SYM is the symbol returned in a block token. OPEN-DELIM and CLOSE-DELIM are respectively the open and close delimiters identifying a block. OPEN-SYM and CLOSE-SYM are respectively the symbols returned in open and close tokens.

Source Code

;; Defined in /usr/src/emacs/lisp/cedet/semantic/lex.el.gz
(defmacro define-lex-block-analyzer (name doc spec1 &rest specs)
  "Create a lexical analyzer NAME for paired delimiters blocks.
It detects a paired delimiters block or the corresponding open or
close delimiter depending on the value of the variable
`semantic-lex-current-depth'.  DOC is the documentation string of the lexical
analyzer.  SPEC1 and SPECS specify the token symbols and open, close
delimiters used.  Each SPEC has the form:

\(BLOCK-SYM (OPEN-DELIM OPEN-SYM) (CLOSE-DELIM CLOSE-SYM))

where BLOCK-SYM is the symbol returned in a block token.  OPEN-DELIM
and CLOSE-DELIM are respectively the open and close delimiters
identifying a block.  OPEN-SYM and CLOSE-SYM are respectively the
symbols returned in open and close tokens."
  (declare (debug (&define name stringp form (&rest form)))
           (indent 1))
  (let ((specs (cons spec1 specs))
        spec open olist clist)
    (while specs
      (setq spec  (car specs)
            specs (cdr specs)
            open  (nth 1 spec)
            ;; build alist ((OPEN-DELIM OPEN-SYM BLOCK-SYM) ...)
            olist (cons (list (car open) (cadr open) (car spec)) olist)
            ;; build alist ((CLOSE-DELIM CLOSE-SYM) ...)
            clist (cons (nth 2 spec) clist)))
    `(define-lex-analyzer ,name
       ,doc
       (and
        (looking-at "\\(\\s(\\|\\s)\\)")
        (let ((text (match-string 0)) match)
          (cond
           ((setq match (assoc text ',olist))
            (if (or (not semantic-lex-maximum-depth)
		    (< semantic-lex-current-depth semantic-lex-maximum-depth))
                (progn
                  (setq semantic-lex-current-depth (1+ semantic-lex-current-depth))
		  (semantic-lex-push-token
		   (semantic-lex-token
		    (nth 1 match)
		    (match-beginning 0) (match-end 0))))
	      (semantic-lex-push-token
	       (semantic-lex-token
		(nth 2 match)
		(match-beginning 0)
		(save-excursion
		  (semantic-lex-unterminated-syntax-protection (nth 2 match)
		    (forward-list 1)
		    (point)))
		))
	      ))
           ((setq match (assoc text ',clist))
	    (if (> semantic-lex-current-depth 0)
		(progn
		  (setq semantic-lex-current-depth (1- semantic-lex-current-depth))
		  (semantic-lex-push-token
		   (semantic-lex-token
		    (nth 1 match)
		    (match-beginning 0) (match-end 0)))))))))
       )))