Add German alphabet and fix French numbers

- Add German alphabet.
- Fix French numbers being rendered by their ordinal Braille codes.

CONTRIBUTING.md

@@ -49,7 +49,7 @@ each locale is stored.
 1. Create the expected file for the locale in `tests/{locale}.expect.txt`.
 1. Add the language to README [Supported alphabets][supported-alphabets-table]
  table.
-1. Add a note with details about the implementation for that language in
+1. Add a section with details about the implementation for that language in
  [NOTES.md][notes]. This is specially useful if the implementation contains
  singularities and will help future developers to maintain the code.
 

NOTES.md

@@ -11,6 +11,8 @@ Implementation of [North American Braille ASCII code][en-wiki].
 
 Implementation of [CBE guide][es-cbe-guide].
 
+### Numbers treatment
+
 - According to the guide, numbers with 10 or more digits and telephone numbers
  must be preceded by a numeric prefix `⠼` in the first number only. But
  this implementation currently precede the numerical prefix before any number.
@@ -19,6 +21,24 @@ Implementation of [CBE guide][es-cbe-guide].
 
 Implementation of [Code Braille Français Uniformisé (CBFU)][fr-cbfu].
 
+## German - Das System der deutschen Brailleschrift
+
+Implementation of [Das System der deutschen Brailleschrift][de-system] (created
+by [BSKDL][bskdl]).
+
+### Capital letters treatment
+
+The handling of capital letters has been simplified in this implementation.
+The [guide][de-system] indicates that:
+
+1. Individual capital letters and sequences of capital letters are identified
+ by placing the character‌ `⠘` in front of them (capital letter ad symbol).
+1. Lowercase letters are marked by prefixing them with the character `⠠`
+ (lowercase advertisement character).
+
+However, these rules don't apply. For each capital letter, only the character
+`⠨` is prepended regardless of its context.
+
 ## Galician - Braille español (Grado 1)
 
 Uses same implementation as Spanish.
@@ -35,4 +55,6 @@ Uses same implementation as Spanish.
 [en-wiki]: https://en.wikipedia.org/wiki/Braille_ASCII
 [es-cbe-guide]: https://sid.usal.es/idocs/F8/FDO12069/signografiabasica.pdf
 [fr-cbfu]: https://www.avh.asso.fr/sites/default/files/cbfu_edition_internationale_1.pdf
+[de-system]: http://bskdl.org/textschrift.html
+[bskdl]: http://bskdl.org
 [world-braille-usage]: https://1kru3o1eyt4f2w3qy21ds14w-wpengine.netdna-ssl.com/wp-content/uploads/2021/07/world-braille-usage-third-edition.pdf

README.md

@@ -13,11 +13,12 @@ Text-to-Braille Inkscape extension with multiple localized alphabets.
 | English | [North American Braille ASCII code][en-wiki] |
 | Spanish | [Braille español (Grado 1)][es-cbe-guide] by [CBE][cbe-once] |
 | French  | [Code Braille Français Uniformisé (CBFU)][fr-cbfu] |
+| German  | [Das System der deutschen Brailleschrift][de-system] by [BSKDL][bskdl]|
 | Galician | [Braille español (Grado 1)][es-cbe-guide] by [CBE][cbe-once] |
 | Euskera | [Braille español (Grado 1)][es-cbe-guide] by [CBE][cbe-once] |
 | Catalan/Valencian | [Braille español (Grado 1)][es-cbe-guide] by [CBE][cbe-once] |
 
-> See [NOTES.md][notes] to check the limitations of each implementation.
+> See [NOTES.md][notes] to details of each implementation.
 
 ## Installation
 
@@ -58,5 +59,7 @@ about how to contribute to this project.
 
 [en-wiki]: https://en.wikipedia.org/wiki/Braille_ASCII
 [es-cbe-guide]: https://sid.usal.es/idocs/F8/FDO12069/signografiabasica.pdf
-[fr-cbfu]: https://www.avh.asso.fr/sites/default/files/cbfu_edition_internationale_1.pdf
 [cbe-once]: https://www.once.es/servicios-sociales/braille/comision-braille-espanola/comision-braille-espanola-cbe
+[fr-cbfu]: https://www.avh.asso.fr/sites/default/files/cbfu_edition_internationale_1.pdf
+[de-system]: http://bskdl.org/textschrift.html
+[bskdl]: http://bskdl.org

tests/de.expect.txt

@@ -0,0 +1,6 @@
+⠁⠃⠉⠙⠑⠋⠛⠓⠊⠚⠅⠇⠍⠝⠕⠏⠟⠗⠎⠞⠥⠧⠺⠭⠽⠵
+⠨⠁⠨⠃⠨⠉⠨⠙⠨⠑⠨⠋⠨⠛⠨⠓⠨⠊⠨⠚⠨⠅⠨⠇⠨⠍⠨⠝⠨⠕⠨⠏⠨⠟⠨⠗⠨⠎⠨⠞⠨⠥⠨⠧⠨⠺⠨⠭⠨⠽⠨⠵
+⠀\'⠈⠜⠐⠂"^>⠂⠠⠔<-⠄⠼⠚⠴⠘⠷⠈⠎+⠖⠐⠥⠆⠒(⠈⠸⠢⠘⠾⠈⠼)=+÷
+⠼⠚⠼⠁⠼⠃⠼⠉⠼⠙⠼⠑⠼⠋⠼⠛⠼⠓⠼⠊
+áéíóúàèìòù⠜ëï⠪⠳ÁÉÍÓÚÀÈÌÒÙ⠨⠜ËÏ⠨⠪⠨⠳
+çÇ⠼⠚⠴⠼⠚⠴⠴⠶⠘⠉⠶⠶⠘⠗⠶℗🄯⠐⠂\<>⠐⠤{}—⠈⠑⠈⠎⠈⠉⠈⠇¥￥⠈⠸⠤

tests/fr.expect.txt

@@ -1,6 +1,6 @@
 ⠁⠃⠉⠙⠑⠋⠛⠓⠊⠚⠅⠇⠍⠝⠕⠏⠟⠗⠎⠞⠥⠧⠺⠭⠽⠵
 ⠨⠁⠨⠃⠨⠉⠨⠙⠨⠑⠨⠋⠨⠛⠨⠓⠨⠊⠨⠚⠨⠅⠨⠇⠨⠍⠨⠝⠨⠕⠨⠏⠨⠟⠨⠗⠨⠎⠨⠞⠨⠥⠨⠧⠨⠺⠨⠭⠨⠽⠨⠵
 ⠀⠐⠌⠄⠜⠌⠶⠈⠐⠜⠂⠐⠔⠐⠣⠤⠲⠐⠬⠘⠦⠘⠎⠖⠖⠐⠿⠆⠒⠦⠐⠤⠢⠴⠃⠐⠼⠴⠶⠖⠒
-⠼⠼⠼⠡⠼⠣⠼⠩⠼⠹⠼⠱⠼⠫⠼⠻⠼⠳⠼⠪
+⠼⠚⠼⠁⠼⠃⠼⠉⠼⠙⠼⠑⠼⠋⠼⠛⠼⠓⠼⠊
 á⠿íóú⠷⠮ìò⠾ä⠫⠻ö⠳Á⠨⠿ÍÓÚ⠨⠷⠨⠮ÌÒ⠨⠾Ä⠨⠫⠨⠻Ö⠨⠳
 ⠯⠨⠯⠐⠬⠐⠬⠬⠐⠉⠐⠗℗🄯⠌⠐⠌⠐⠣⠐⠜|⠠⠠⠦⠴⠄⠄⠤⠤⠘⠑⠘⠎⠘⠉⠘⠇⠘⠽⠘⠽⠐⠤⠤⠤

text_braille_l18n.inx

@@ -9,6 +9,7 @@
         <option value="en">English (ASCII)</option>
         <option value="es">Spanish</option>
         <option value="fr">French</option>
+        <option value="de">German</option>
         <option value="gl">Galician</option>
         <option value="eu">Basque</option>
         <option value="ca">Catalan/Valencian</option>

text_braille_l18n.py

@@ -7,17 +7,15 @@
 
 # UTILITIES
 
+# Common standards
+
 UPPERCASE_PREFIXES = {
     chr(15): 0x2828,  # uppercase prefix: https://codepoints.net/U+000F
 }
 
-# English based locales
-
-EN_ASCII = " A1B'K2L@CIF/MSP\"E3H9O6R^DJG>NTQ,*5<-U8V.%[$+X!&;:4\\0Z7(_?W]#Y)="
 
-# Spanish based locales
-
-ES_NUMBERS = {
+LOUIS_BRAILLE_NUMBERS_PREFIX = 0x283c  # Louis Braille's numbers prefix
+LOUIS_BRAILLE_NUMBERS = {  # Louis Braille's original numbers codification
     "0": 0x281a,
     "1": 0x2801,
     "2": 0x2803,
@@ -30,6 +28,14 @@
     "9": 0x280a,
 }
 
+# ---------------------
+
+# English based locales
+
+EN_ASCII = " A1B'K2L@CIF/MSP\"E3H9O6R^DJG>NTQ,*5<-U8V.%[$+X!&;:4\\0Z7(_?W]#Y)="
+
+# Spanish based locales
+
 ES_LETTERS = {
     "A": 0x2801,
     "B": 0x2803,
@@ -143,19 +149,6 @@
 
 # French based locales
 
-FR_NUMBERS = {
-    "0": 0x283c,
-    "1": 0x2821,
-    "2": 0x2823,
-    "3": 0x2829,
-    "4": 0x2839,
-    "5": 0x2831,
-    "6": 0x282b,
-    "7": 0x283b,
-    "8": 0x2833,
-    "9": 0x282a,
-}
-
 FR_LETTERS = {
     "A": 0x2801,
     "B": 0x2803,
@@ -275,24 +268,85 @@
     "￥": (0x2818, 0x283d),
 }
 
+# German based locales
+
+DE_ACCENT_MARKS = {
+    "Ä": 0x281c,
+    "Ö": 0x282a,
+    "Ü": 0x2833,
+}
+
+DE_SIGNS = {
+    " ": 0x2800,  # braille space
+    ",": 0x2802,
+    ";": 0x2806,
+    ":": 0x2812,
+    "?": 0x2822,
+    "!": 0x2816,
+    "„": 0x2826,
+    "“": 0x2834,
+    "§": 0x282c,
+    ".": 0x2804,
+    "–": 0x2824,
+    "‚": 0x2820,
+}
+
+DE_COMBINATIONS = {
+    # signs
+    "ß": (0x282e,),  # converted to 'SS' if uppercased, so defined in combinations
+    "|": (0x2810, 0x2824),
+    "[": (0x2818, 0x2837),
+    "]": (0x2818, 0x283e),
+    "/": (0x2818, 0x280c),
+    "`": (0x2820, 0x2826),
+    "´": (0x2820, 0x2834),
+    "/": (0x2810, 0x2802),
+    "&": (0x2810, 0x2825),
+    "*": (0x2820, 0x2814),
+    "→": (0x2812, 0x2812, 0x2815),
+    "←": (0x282a, 0x2812, 0x2812),
+    "↔": (0x282a, 0x2812, 0x2812, 0x2815),
+    "%": (0x283c, 0x281a, 0x2834),
+    "‰": (0x283c, 0x281a, 0x2834, 0x2834),
+    "°": (0x2808, 0x2834),
+    "′": (0x2808, 0x2814),
+    "″": (0x2808, 0x2814, 0x2814),
+    "@": (0x2808, 0x281c),
+    "_": (0x2808, 0x2838),
+    "#": (0x2808, 0x283c),
+
+    # currencies
+    "€": (0x2808, 0x2811),
+    "$": (0x2808, 0x280e),
+    "¢": (0x2808, 0x2809),
+    "£": (0x2808, 0x2807),
+
+    # legal
+    "©": (0x2836, 0x2818, 0x2809, 0x2836),
+    "®": (0x2836, 0x2818, 0x2817, 0x2836),
+}
+
 # END: UTILITIES
 
 # ---------------------------------
 
 # LOCALE FUNCTIONS
 
 def en_char_map(char):
-    # https://en.wikipedia.org/wiki/Braille_ASCII#Braille_ASCII_values
+    """English chars mapper.
+
+    Source: https://en.wikipedia.org/wiki/Braille_ASCII#Braille_ASCII_values
+    """
     try:
         mapint = EN_ASCII.index(char.upper())
     except ValueError:
         return char
     return chr(mapint + 0x2800)
 
-def number_singleupper_combinations_factory(
+def numbers_singleuppers_combinations_factory(
     numbers_map,
     singleuppers_map,
-    combinations_map,
+    combinations_map,  # also individual characters that are modified if uppercased
     number_prefix,
     uppercase_prefix,
 ):
@@ -321,8 +375,8 @@ def es_char_map_loader():
 
     Source: https://sid.usal.es/idocs/F8/FDO12069/signografiabasica.pdf
     """
-    return number_singleupper_combinations_factory(
-        ES_NUMBERS,
+    return numbers_singleuppers_combinations_factory(
+        LOUIS_BRAILLE_NUMBERS,
         {
             **ES_LETTERS,
             **ES_ACCENT_MARKS,
@@ -341,8 +395,8 @@ def eu_char_map_loader():
 
     Source: https://sid.usal.es/idocs/F8/FDO12069/signografiabasica.pdf
     """
-    return number_singleupper_combinations_factory(
-        ES_NUMBERS,
+    return numbers_singleuppers_combinations_factory(
+        LOUIS_BRAILLE_NUMBERS,
         {
             **ES_LETTERS,
             **ES_SIGNS,
@@ -359,8 +413,8 @@ def ca_char_map_loader():
 
     Source: https://sid.usal.es/idocs/F8/FDO12069/signografiabasica.pdf
     """
-    return number_singleupper_combinations_factory(
-        ES_NUMBERS,
+    return numbers_singleuppers_combinations_factory(
+        LOUIS_BRAILLE_NUMBERS,
         {
             **ES_LETTERS,
             **CA_ACCENT_MARKS,
@@ -373,13 +427,12 @@ def ca_char_map_loader():
     )
 
 def fr_char_map_loader():
-    """Catalan/Valencian chars mappers. Uses the same implementation as
-    Spanish but different accent marks.
+    """French chars mapper.
 
     Source: https://sid.usal.es/idocs/F8/FDO12069/signografiabasica.pdf
     """
-    return number_singleupper_combinations_factory(
-        FR_NUMBERS,
+    return numbers_singleuppers_combinations_factory(
+        LOUIS_BRAILLE_NUMBERS,
         {
             **FR_LETTERS,
             **FR_ACCENT_MARKS,
@@ -391,12 +444,33 @@ def fr_char_map_loader():
         0x2828,
     )
 
+def de_char_map_loader():
+    """German chars mapper.
+
+    - For letters, uses the same dictionary as French implementation.
+
+    Source: http://bskdl.org/textschrift.html
+    """
+    return numbers_singleuppers_combinations_factory(
+        LOUIS_BRAILLE_NUMBERS,
+        {
+            **FR_LETTERS,  # Same as French implementation
+            **DE_ACCENT_MARKS,
+            **DE_SIGNS,
+            **UPPERCASE_PREFIXES,
+        },
+        DE_COMBINATIONS,
+        0x283c,
+        0x2828,
+    )
+
 # END: LOCALE FUNCTIONS
 
 LOCALE_CHARMAPS = {
-    "en": en_char_map,
-    "es": es_char_map_loader,
-    "fr": fr_char_map_loader,
+    "en": en_char_map,         # English
+    "es": es_char_map_loader,  # Spanish
+    "fr": fr_char_map_loader,  # French
+    "de": de_char_map_loader,  # German
     "gl": es_char_map_loader,  # Galician
     "eu": eu_char_map_loader,  # Euskera
     "ca": ca_char_map_loader,  # Catalan/Valencian