[css-pseudo-4] Add Symbols to possible First Letters. #5099

Author: fantasai

css-pseudo-4/Overview.bs

@@ -278,9 +278,12 @@ Inheritance and the ''::first-line'' Pseudo-element</h4>
 First-Letter Text: ''::first-letter'' pseudo-element and its ''::prefix'' and ''::postfix'' children</h3>
 
   The <dfn>::first-letter</dfn> [=pseudo-element=] represents
-  the first <a>typographic letter unit</a> [[!CSS-TEXT-3]]
-  on the <a>first formatted line</a> of its <a>originating element</a>,
-  its <dfn>first-letter text</dfn>.
+  the first Letter, Number, or Symbol
+  (Unicode category <code>L*</code>, <code>N*</code>, or <code>S*</code>) [=typographic character unit=]  [[!CSS-TEXT-3]]
+  on the <a>first formatted line</a> of its <a>originating element</a>
+  (the <dfn>first letter</dfn>)
+  as well as its associated punctuation.
+  Collectively, this text is the <dfn>first-letter text</dfn>.
   The ''::first-letter'' pseudo-element can be used
   to create “initial caps” and “drop caps”,
   which are common typographic effects.
@@ -294,17 +297,17 @@ First-Letter Text: ''::first-letter'' pseudo-element and its ''::prefix'' and ''
   </div>
 
   As explained in [[!CSS-TEXT-3]],
-  a <a>typographic letter unit</a> can include more than one Unicode codepoint.
+  a <a>typographic character unit</a> can include more than one Unicode codepoint.
   For example, combining characters must be kept with their base character.
   Also, languages may have additional rules
   about how to treat certain letter combinations.
   In Dutch, for example, if the letter combination "ij" appears at the beginning of an element,
   both letters should be considered within the ''::first-letter'' pseudo-element. [[UAX29]]
-  When selecting the [=first-letter text=],
-  the UA should tailor its definition of <a>typographic letter unit</a>
+  When selecting the [=first letter=],
+  the UA should tailor its definition of <a>typographic character unit</a>
   to reflect the first-letter traditions of the ''::first-letter'' pseudo-element’s <em>containing block</em>’s content language.
 
-  Note: Note that the first <a>typographic letter unit</a> may in fact
+  Note: Note that the [=first letter=] may in fact
   be a digit, e.g., the “6” in “67 million dollars is a lot of money.”
 
   Preceding and following punctuation
@@ -315,13 +318,13 @@ First-Letter Text: ''::first-letter'' pseudo-element and its ''::prefix'' and ''
     <li>
       All punctuation--
       i.e, characters that belong to the Punctuation (<code>P*</code>) <a>Unicode general category</a> [[!UAX44]]--
-      that precedes the first [=typographic letter unit=]
+      that precedes the [=first letter=].
     <li>
       Punctuation other than opening punctuation and dashes--
       i.e. characters that belong to the Punctuation (<code>P*</code>) <a>Unicode general category</a>,
       excluding Open Punctuation (<code>Ps</code>)
       and Dash Punctuation (<code>Pd</code>)--
-      that follows the first [=typographic letter unit=]
+      that follows the [=first letter=].
     <li>
       Any intervening typographic space--
       i.e. characters that belong to the <code>Zs</code> Unicode general category [[!UAX44]]
@@ -336,18 +339,18 @@ First-Letter Text: ''::first-letter'' pseudo-element and its ''::prefix'' and ''
     (ignoring the exclusion of word separators from <code>Zs</code>)
     represented as
     <code highlight="bnf" style="font-family: inherit">
-    (Zs|P)* (L|N)+ (Zs|P^(Ps|Pd))*</code>
+    (Zs|P)* (L|N|S)+ (Zs|P^(Ps|Pd))*</code>
     or, alternatively,
     <code highlight="bnf" style="font-family: inherit">
-    [Zs P]* [L N]+ [[Zs] [P--[Ps Pd]]]*</code>
+    [Zs P]* [L N S]+ [[Zs] [P--[Ps Pd]]]*</code>
     <!-- this is not actually BNF, but it highlights better that way -->
   </div>
 
   <div class="figure">
       <img alt="Quotes that precede the first letter should be included." src="images/first-letter2.gif">
   </div>
 
-  To allow independent styling of the first letter itself
+  To allow independent styling of the [=first letter=] itself
   and its adjacent punctuation,
   such preceding punctuation
   is represented by the <dfn for="::first-letter">::prefix</dfn>