[iostate.flags] clarify boolean expressions

Author: Eisenwave

source/iostreams.tex

@@ -2279,8 +2279,8 @@
 \begin{itemdescr}
 \pnum
 \effects
-If \tcode{((state | (rdbuf() ? goodbit : badbit)) \& exceptions()) == 0},
-returns.
+If \tcode{((state | (rdbuf() ? goodbit : badbit)) \& exceptions()) == 0}
+is \keyword{true}, returns.
 Otherwise, the function throws an object of class
 \tcode{ios_base::failure}\iref{ios.failure},
 constructed with
@@ -2290,11 +2290,11 @@
 \pnum
 \ensures
 If
-\tcode{rdbuf() != 0}
+\tcode{rdbuf() != 0} is \keyword{true}
 then
-\tcode{state == rdstate()};
+\tcode{state == rdstate()} is \keyword{true};
 otherwise
-\tcode{rdstate() == (state | ios_base::badbit)}.
+\tcode{rdstate() == (state | ios_base::badbit)} is \keyword{true}.
 \end{itemdescr}
 
 \indexlibrarymember{setstate}{basic_ios}%
@@ -2319,7 +2319,7 @@
 \begin{itemdescr}
 \pnum
 \returns
-\tcode{rdstate() == 0}
+\tcode{rdstate() == 0} is \keyword{true}.
 \end{itemdescr}
 
 \indexlibrarymember{eof}{basic_ios}%
@@ -2402,7 +2402,7 @@
 
 \pnum
 \ensures
-\tcode{except == exceptions()}.
+\tcode{except == exceptions()} is \keyword{true}.
 \end{itemdescr}
 
 \rSec2[std.ios.manip]{\tcode{ios_base} manipulators}