Add support for a reserved-words list and reserve the various not-supported-but-plausible IEEE datatypes.

1 files changed, 36 insertions, 2 deletions

diff --git a/doc/rust.texi b/doc/rust.texi
index 63181f88..fcfb6499 100644
--- a/doc/rust.texi
+++ b/doc/rust.texi
@@ -599,6 +599,7 @@ Unicode characters.
 * Ref.Lex.Ignore::       Ignored characters.
 * Ref.Lex.Ident::        Identifier tokens.
 * Ref.Lex.Key::          Keyword tokens.
+* Ref.Lex.Res::          Reserved tokens.
 * Ref.Lex.Num::          Numeric tokens.
 * Ref.Lex.Text::         String and character tokens.
 * Ref.Lex.Syntax::       Syntactic extension tokens.
@@ -636,7 +637,7 @@ token or a syntactic extension token.  Multi-line comments may be nested.
 Identifiers follow the pattern of C identifiers: they begin with a
 @emph{letter} or @emph{underscore}, and continue with any combination of
 @emph{letters}, @emph{decimal digits} and underscores, and must not be equal
-to any keyword. @xref{Ref.Lex.Key}.
+to any keyword or reserved token. @xref{Ref.Lex.Key}. @xref{Ref.Lex.Res}.
 
 A @emph{letter} is a Unicode character in the ranges U+0061-U+007A and
 U+0041-U+005A (@code{'a'}-@code{'z'} and @code{'A'}-@code{'Z'}).
@@ -728,6 +729,35 @@ The keywords are:
 @tab @code{be}
 @end multitable
 
+@node       Ref.Lex.Res
+@subsection Ref.Lex.Res
+@c * Ref.Lex.Res::                Reserved tokens.
+
+The reserved tokens are:
+@cindex Reserved
+
+@sp 2
+
+@multitable @columnfractions .15 .15 .15 .15 .15
+@item @code{f16}
+@tab @code{f80}
+@tab @code{f128}
+@item @code{m32}
+@tab @code{m64}
+@tab @code{m128}
+@tab @code{dec}
+@end multitable
+
+@sp 2
+
+At present these tokens have no defined meaning in the Rust language.
+
+These tokens may correspond, in some current or future implementation,
+to additional built-in types for decimal floating-point, extended
+binary and interchange floating-point formats, as defined in the IEEE
+754-1985 and IEEE 754-2008 specifications.
+
+
 @node       Ref.Lex.Num
 @subsection Ref.Lex.Num
 @c * Ref.Lex.Num::                 Numeric tokens.
@@ -785,6 +815,10 @@ only two floating-point suffixes: @code{f32} and @code{f64}. Each of these
 gives the floating point literal the associated type, rather than
 @code{float}.
 
+A set of suffixes are also reserved to accommodate literal support for
+types corresponding to reserved tokens. The reserved suffixes are @code{f16},
+@code{f80}, @code{f128}, @code{m}, @code{m32}, @code{m64} and @code{m128}.
+
 @sp 1
 A @dfn{hex digit} is either a @emph{decimal digit} or else a character in the
 ranges U+0061-U+0066 and U+0041-U+0046 (@code{'a'}-@code{'f'},
@@ -2024,7 +2058,7 @@ The signed two's complement word types @code{i8}, @code{i16}, @code{i32} and
 @end ifhtml
  respectively.
 @item
-The IEEE 754 single-precision and double-precision floating-point types:
+The IEEE 754-2008 @code{binary32} and @code{binary64} floating-point types:
 @code{f32} and @code{f64}, respectively.
 @end itemize