[expr.unary.noexcept] replace informative wording

Author: Eisenwave

source/expressions.tex

@@ -5042,14 +5042,16 @@
 \pnum
 \indextext{\idxcode{noexcept}}%
 \indextext{expression!\idxcode{noexcept}}%
-The \keyword{noexcept} operator determines whether the evaluation of its operand,
-which is an unevaluated operand\iref{term.unevaluated.operand}, can throw an
-exception\iref{except.throw}.
-
+The \keyword{noexcept} operator
 \begin{bnf}
 \nontermdef{noexcept-expression}\br
   \keyword{noexcept} \terminal{(} expression \terminal{)}
 \end{bnf}
+has an \grammarterm{expression} \term{operand}
+which is an unevaluated operand\iref{term.unevaluated.operand}.
+The \keyword{noexcept} operator yields \keyword{true}
+unless the full-expression of the operand
+is potentially-throwing\iref{except.spec}.
 
 \pnum
 The result of the \keyword{noexcept} operator is a prvalue of type \keyword{bool}.
@@ -5061,9 +5063,6 @@
 \pnum
 If the operand is a prvalue,
 the temporary materialization conversion\iref{conv.rval} is applied.
-The result of the \keyword{noexcept} operator is \keyword{true}
-unless the full-expression of the operand
-is potentially-throwing\iref{except.spec}.
 \indextext{expression!unary|)}
 
 \rSec3[expr.new]{New}