(+ 3 (* 8 (ucd-value-0 char))))))
(when (< decimal-digit 10)
decimal-digit)))
+(declaim (ftype (sfunction (t) (unsigned-byte 8)) ucd-ccc))
+(defun ucd-ccc (char)
+ (aref **character-database** (+ 2 (* 8 (ucd-value-0 char)))))
(defun char-code (char)
#!+sb-doc
(decompositions **character-decompositions**)
(long-decompositions **character-long-decompositions**)
(index (+ #x1100
- (ash (aref decompositions cp-high) 10)
+ (ash (aref decompositions cp-high) 10)
(ash (ldb (byte 8 0) cp) 2)))
(v0 (aref decompositions index))
(v1 (aref decompositions (+ index 1)))
(dpb v2 (byte 8 8) v3))))
(if (= length 1)
(string (code-char entry))
- (let ((result (make-string length))
- (e (* 4 entry)))
- (dotimes (i length result)
- (let ((code (dpb (aref long-decompositions (+ e 1))
- (byte 8 16)
- (dpb (aref long-decompositions (+ e 2))
- (byte 8 8)
- (aref long-decompositions (+ e 3))))))
- (setf (char result i) (code-char code)))
- (incf e 4))))))
+ (if (<= #xac00 cp #xd7a3)
+ ;; see Unicode 6.2, section 3-12
+ (let* ((sbase #xac00)
+ (lbase #x1100)
+ (vbase #x1161)
+ (tbase #x11a7)
+ (lcount 19)
+ (vcount 21)
+ (tcount 28)
+ (ncount (* vcount tcount))
+ (scount (* lcount ncount))
+ (sindex (- cp sbase))
+ (lindex (floor sindex ncount))
+ (vindex (floor (mod sindex ncount) tcount))
+ (tindex (mod sindex tcount))
+ (result (make-string length)))
+ (declare (ignore scount))
+ (setf (char result 0) (code-char (+ lbase lindex)))
+ (setf (char result 1) (code-char (+ vbase vindex)))
+ (when (> tindex 0)
+ (setf (char result 2) (code-char (+ tbase tindex))))
+ result)
+ (let ((result (make-string length))
+ (e (* 4 entry)))
+ (dotimes (i length result)
+ (let ((code (dpb (aref long-decompositions (+ e 1))
+ (byte 8 16)
+ (dpb (aref long-decompositions (+ e 2))
+ (byte 8 8)
+ (aref long-decompositions (+ e 3))))))
+ (setf (char result i) (code-char code)))
+ (incf e 4)))))))
(defun decompose-char (char)
(if (= (char-decomposition-info char) 0)
(string char)
(char-decomposition char)))
+
+(defun decompose-string (string &optional (kind :canonical))
+ (declare (type (member :canonical :compatibility) kind))
+ (flet ((canonical (char)
+ (= 1 (char-decomposition-info char)))
+ (compat (char)
+ (/= 0 (char-decomposition-info char))))
+ (let (result
+ (fun (ecase kind
+ (:canonical #'canonical)
+ (:compatibility #'compat))))
+ (do* ((start 0 (1+ end))
+ (end (position-if fun string :start start)
+ (position-if fun string :start start)))
+ ((null end) (push (subseq string start end) result))
+ (unless (= start end)
+ (push (subseq string start end) result))
+ (push (decompose-char (char string end)) result))
+ (apply 'concatenate 'string (nreverse result)))))
+
+(defun sort-combiners (string)
+ (let (result (start 0) first-cc first-non-cc)
+ (tagbody
+ again
+ (setf first-cc (position 0 string :key #'ucd-ccc :test #'/= :start start))
+ (when first-cc
+ (setf first-non-cc (position 0 string :key #'ucd-ccc :test #'= :start first-cc)))
+ (push (subseq string start first-cc) result)
+ (when first-cc
+ (push (stable-sort (subseq string first-cc first-non-cc) #'< :key #'ucd-ccc) result))
+ (when first-non-cc
+ (setf start first-non-cc first-cc nil first-non-cc nil)
+ (go again)))
+ (apply 'concatenate 'string (nreverse result))))
+
+#+nil
+(defun primary-composition (char1 char2)
+ (when (and (char= char1 #\e)
+ (char= char2 #\combining_acute_accent))
+ #\latin_small_letter_e_with_acute))
+
+;;; This implements a sequence data structure, specialized for
+;;; efficient deletion of characters at an index, along with tolerable
+;;; random access. The purpose is to support the canonical
+;;; composition algorithm from Unicode, which involves replacing (not
+;;; necessarily consecutive) pairs of code points with a single code
+;;; point (e.g. [#\e #\combining_acute_accent] with
+;;; #\latin_small_letter_e_with_acute). The data structure is a list
+;;; of three-element lists, each denoting a chunk of string data
+;;; starting at the first index and ending at the second.
+;;;
+;;; Actually, the implementation isn't particularly efficient, and
+;;; would probably benefit from being rewritten in terms of displaced
+;;; arrays, which would substantially reduce copying.
+;;;
+;;; (also, generic sequences. *sigh*.)
+(defun lref (lstring index)
+ (dolist (l lstring)
+ (when (and (<= (first l) index)
+ (< index (second l)))
+ (return (aref (third l) (- index (first l)))))))
+(defun (setf lref) (newchar lstring index)
+ (dolist (l lstring)
+ (when (and (<= (first l) index)
+ (< index (second l)))
+ (return (setf (aref (third l) (- index (first l))) newchar)))))
+(defun llength (lstring)
+ (second (first (last lstring))))
+(defun lstring (lstring)
+ (let ((result (make-string (llength lstring))))
+ (dolist (l lstring result)
+ (replace result (third l) :start1 (first l) :end1 (second l)))))
+(defun ldelete (lstring index)
+ (do* ((ls lstring (cdr ls))
+ (l (car ls) (car ls))
+ so-fars)
+ ((and (<= (first l) index)
+ (< index (second l)))
+ (append
+ (nreverse so-fars)
+ (cond
+ ((= (first l) index)
+ (list (list (first l) (1- (second l)) (subseq (third l) 1))))
+ ((= index (1- (second l)))
+ (list (list (first l) (1- (second l)) (subseq (third l) 0 (1- (length (third l)))))))
+ (t
+ (list
+ (list (first l) index
+ (subseq (third l) 0 (- index (first l))))
+ (list index (1- (second l))
+ (subseq (third l) (1+ (- index (first l))))))))
+ (mapcar (lambda (x) (list (1- (first x)) (1- (second x)) (third x)))
+ (cdr ls))))
+ (push l so-fars)))
+
+(defun canonically-compose (string)
+ (labels ()
+ (let* ((result (list (list 0 (length string) string)))
+ (previous-starter-index (position 0 string :key #'ucd-ccc))
+ (i (1+ previous-starter-index)))
+ (when (= i (length string))
+ (return-from canonically-compose string))
+ (tagbody
+ again
+ (when (and (> (- i previous-starter-index) 2)
+ ;; test for Blocked (Unicode 3.11 para. D115)
+ (>= (ucd-ccc (lref result (1- i)))
+ (ucd-ccc (lref result i))))
+ (when (= (ucd-ccc (lref result i)) 0)
+ (setf previous-starter-index i))
+ (incf i)
+ (go next))
+
+ (let ((comp (primary-composition (lref result previous-starter-index)
+ (lref result i))))
+ (cond
+ (comp
+ (setf (lref result previous-starter-index) comp)
+ (setf result (ldelete result i)))
+ (t
+ (when (= (ucd-ccc (lref result i)) 0)
+ (setf previous-starter-index i))
+ (incf i))))
+ next
+ (unless (= i (llength result))
+ (go again)))
+ (if (= i (length string))
+ string
+ (lstring result)))))
+
+(defun normalize-string (string &optional (form :nfd))
+ (declare (type (member :nfd :nfkd :nfc :nfkc) form))
+ (etypecase string
+ #!+sb-unicode
+ (base-string string)
+ ((or (array character (*)) #!-sb-unicode base-string)
+ (ecase form
+ ((:nfd)
+ (sort-combiners (decompose-string string)))
+ ((:nfkd)
+ (sort-combiners (decompose-string string :compatibility)))))
+ ((array nil (*)) string)))