Merge pull request #349 from blackwhale/arrays-page

Add a section on Strings and Unicode

arrays.dd

@@ -839,6 +839,28 @@ w = "\r"[0]; // w is assigned the carriage return wchar character
 d = 'd';     // d is assigned the character 'd'
 ---------
 
+$(H5 $(LNAME2 strings_unicode, Strings and Unicode))
+        $(P Note that built-in comparison operators operate on a
+        $(WEB www.unicode.org/glossary/#code_unit, code unit) basis. 
+        The end result for valid strings is the same as that of 
+        $(WEB www.unicode.org/glossary/#code_point, code point) 
+        for $(WEB www.unicode.org/glossary/#code_point, code point)
+        comparison as long as both strings are in the same
+        $(WEB www.unicode.org/glossary/#normalization_form, normalization form).
+        Since normalization is a costly operation not suitable for language 
+        primitives it's assumed to be enforced by the user.
+        )
+        $(P The standard library lends a hand for comparing strings with mixed encodings
+        (by transparently decoding, see $(PHOBOS algorithm, cmp, std.algorithm.cmp)), 
+        $(PHOBOS uni, icmp, case-insensitive comparison) and $(PHOBOS uni, normalize, normalization).
+        )
+        $(P The last but not least - a desired string sorting order differs 
+        by culture and language and is usually nothing like code point 
+        for code point comparison. The natural order of strings is obtained by applying
+        $(WEB www.unicode.org/reports/tr10/, the Unicode collation algorithm)
+        that should be implemented in the standard library.
+        )
+
 $(H5 $(LNAME2 printf, C's printf() and Strings))
 
         $(P $(D printf()) is a C function and is not part of D. $(D printf())
@@ -930,4 +952,3 @@ Macros:
         WIKI=Arrays
         CATEGORY_SPEC=$0
         FOO=
-

doc.ddoc

@@ -436,6 +436,8 @@ GLINK2=$(DDSUBLINK $1,$2,$(I $2))
 DPLLINK=$(LINK2 $1,$+)
 GNAME=$(LNAME2 $0, $(I $0))
 NOT_EBOOK=$0
+WEB=$(LINK2 http://$1, $2)
+PHOBOS=<a href="phobos/std_$1.html#$2">$3</a>
 
 ASSIGNEXPRESSION=$(GLINK2 expression, AssignExpression)
 ISEXPRESSION=$(GLINK2 expression, IsExpression)
@@ -485,6 +487,7 @@ REG=&copy;
 H2=<h2>$0</h2>
 H3=<h3>$0</h3>
 H4=<h4>$0</h4>
+H5=<h5>$0</h5>
 CODE_LCURL=$(D {)
 CODE_RCURL=$(D })
 CODE_PERCENT=$(D %)