Re: Placement of HEBREW MAQAF (diacritical)

[Yair F <yair.f.lists@gmail.com>]

On Wed, Jul 28, 2010 at 8:51 PM, Eli Zaretskii <eliz@gnu.org> wrote:
>> From: Yair F. <yair.f.lists@gmail.com>
> How about if you ask questions about things you don't understand?  We
> could then ask Handa-san to answer them, and use the answers as a
> starting point for documenting this in the ELisp manual.

Here are my questions:
1. Given the regular expressions below, how should
composition-function-table be adjust so only those patterns are
composed?
2. How to optimize the patterns in order not to slow down display of
letters without points and give hebrew-composable-pattern-basic priority
over hebrew-composable-pattern-full performance-wise?
3. Is the composition of script-specific characters from Hebrew bloc
(0590) with non-script-specific marks from the combining marks bloc
(0300) currently possible?
4. How to set the language environment so composition displays the correct
presentation form for the given  language?

I believe if we get the answers for these questions we are nearly done
with Hebrew composition. The only missing thing would be influence of
ZWJ, ZWNJ and CGJ on certain combinations.

Yair

(defconst hebrew-composable-no-rafe-pattern
  (concat
   "[\u05D6-\u05D9\u05DC-\u05E2\u05E5-\u05E8]" ;; base
   "\u05BC?"                        ;; 0-1 marks of dagesh
   "[\u05B0-\u05B9\u05BB\u05C7]?"   ;; 0-1 marks of niqqud
   )
  "Regexp matching letters that cannot accept rafe and basic
composition order.")
(defconst hebrew-composable-rafe-pattern
  (concat
   "[\u05D0-\u05D4\u05DA\u05DB\u05E4\u05E5\u05EA]" ;; base
   "[\u05BC\u05BF]?"                ;; 0-1 marks of dagesh/rafe
   "[\u05B0-\u05B9\u05BB\u05C7]?"   ;; 0-1 marks of niqqud
   )
  "Regexp matching letters that cannot accept rafe and basic
composition order.")
(defconst hebrew-composable-vav-pattern
  (concat
   "\u05D5"                         ;; base (vav)
   "\u05BC?"                        ;; 0-1 marks of dagesh (actually shuruq)
   "[\u05B0-\u05BB\u05C7]?"         ;; 0-1 marks of extended niqqud
   )
  "Regexp matching composition order of letter vav.")
(defconst hebrew-composable-shin-pattern
  (concat
   "\u05E9"                         ;; base (shin)
   "\u05BC?"                        ;; 0-1 marks of dagesh
   "[\u05C1\u05C2]?"                ;; 0-1 marks of shin dot
   "[\u05B0-\u05B9\u05BB\u05C7]?"   ;; 0-1 marks of niqqud
   )
  "Regexp matching composition order of letter Shin.")
(defconst  hebrew-composable-cantillation
  (concat
     "[\u0591\u0596\u059B\u05A3-\u05A7\u05AA\u05BD\u05C5]*" ;;  marks
of low-center cantillation marks
     "[\u0323-\u0325\u0332\u0333]?" ;; 0-1 marks of other low marks
     "[\u059A\u05AD]?" ;; 0-1 marks of low-right cantillation marks
     "[\u059D\u05A0]?" ;; 0-1 marks of high-right cantillation marks
     "[\u0593-\u0595\u0597\u0598\u059C\u059E\u05A1\u05A8\u05A9\u05AB\u05AC\u05AF\u05C4]*"
;; marks of high-center cantillation marks
     "[\u0305\u0307\u0308\u030A]?" ;; 0-1 marks of other high marks
     "[\u0592\u0599\u05A9\u5AE]?" ;; 0-1 marks of high-left cantillation marks
   )
  "Regexp matching composition order of cantillation and other marks.")
(defconst hebrew-maqaf-compisition
  "\u05BE\u05AF?"
  "Regexp matching composition order of Maqaf.")
(defconst hebrew-nun-hafukha-compisition
  "\u05C6\u0307?"
  "Regexp matching composition order of Nun Hafukha.")
(defconst hebrew-composable-pattern-basic
  (concat
   "\\("
   hebrew-composable-no-rafe-pattern
   "\\|"
   hebrew-composable-rafe-pattern
   "\\|"
   hebrew-composable-vav-pattern
   "\\|"
   hebrew-composable-shin-pattern
   "\\)")
  "Regexp matching a composable sequence of Hebrew characters basic level.")
(defconst hebrew-composable-pattern-full
  (concat
   "\\("
   hebrew-composable-no-rafe-pattern
   hebrew-composable-cantillation
   "\\|"
   hebrew-composable-rafe-pattern
   hebrew-composable-cantillation
   "\\|"
   hebrew-composable-vav-pattern
   hebrew-composable-cantillation
   "\\|"
   hebrew-composable-shin-pattern
   hebrew-composable-cantillation
   "\\|"
   hebrew-maqaf-compisition
   "\\|"
   hebrew-nun-hafukha-compisition
   "\\)")
  "Regexp matching a composable sequence of Hebrew characters basic level.")
(defconst hebrew-yiddish-composable-pattern
    (concat
     "\u05D0"	       ;; alef
     "[\u05B7\u05B8]?" ;; qamats or Patah
     "\\|"
     "[\u05D1\u05DA\u05DB\u05E4\u05EA]" ;; base
     "[\u05BC\u05BF]?" 			;; dagesh-rafe
     "\\|"
     "\u05D5"                         ;; base (vav)
     "\u05BC?"                        ;; 0-1 marks of dagesh (actually shuruq)
     "\\|"
     "\u05D9"                         ;; base (yod)
     "\u05B4"                        ;; This should be composed as  \uFB1D
     "\\|"
     "\u05E9"                         ;; base (shin)
     "[\u05C1\u05C2]?"                ;; 0-1 marks of shin dot
     "\\|"
     "\u05F2"                         ;; base (zwei yoden)
     "\u05B7"                        ;; This should be composed as  \uFB1F
     )
  "Regexp matching a composable sequence of Hebrew characters for
Yiddish language.")
(defconst hebrew-ladino-composable-pattern
  "[\u05D1\u05D2\u05D6\u05E4]\u05BF"  ;; all sould use \uFB1E insread of \05BF
  "Regexp matching a composable sequence of Hebrew characters for
Ladino (Judezmo) language.")