Replace raw string 'C++' with the appropriate macro

Author: tkoeppe

source/iostreams.tex

@@ -2709,7 +2709,7 @@
 \pnum
 \enternote The more obvious use of
 \tcode{ios_base::hex} to specify hexadecimal floating-point format would
-change the meaning of existing well defined programs. C++2003
+change the meaning of existing well defined programs. \CppIII
 gives no meaning to the combination of \tcode{fixed} and
 \tcode{scientific}.\exitnote
 

source/lex.tex

@@ -1122,7 +1122,7 @@
 \pnum
 Certain nongraphic characters, the single quote \tcode{'}, the double quote \tcode{"},
 the question mark \tcode{?},\footnote{Using an escape sequence for a question mark
-is supported for compatibility with ISO C++14 and ISO C.}
+is supported for compatibility with ISO \CppXIV and ISO C.}
 and the backslash
 \indextext{backslash~character}%
 \indextext{\idxcode{\textbackslash}|see{backslash}}%

source/regex.tex

@@ -4180,7 +4180,7 @@
 default-constructed instance of their \tcode{traits} template parameter, henceforth
 referred to as \tcode{traits_inst}. This \tcode{traits_inst} object is used to support localization
 of the regular expression; \tcode{basic_regex} member functions shall not call
-any locale dependent C or C++ API, including the formatted string input functions.
+any locale dependent C or \Cpp API, including the formatted string input functions.
 Instead they shall call the appropriate traits member function to achieve the required effect.
 
 \pnum

source/templates.tex

@@ -117,7 +117,8 @@
 units.
 A template, a template explicit specialization~(\ref{temp.expl.spec}), and a class
 template partial specialization shall not have C linkage. Use of a linkage specification
-other than C or C++ with any of these constructs is conditionally-supported, with
+other than \tcode{"C"} or \tcode{"C++"} with any of these constructs is
+conditionally-supported, with
 \impldef{semantics of linkage specification on templates} semantics.
 Template definitions shall obey the one-definition rule~(\ref{basic.def.odr}).
 \enternote