fixup: minor fixes from burblebee

Author: jensmaurer

source/compatibility.tex

@@ -51,7 +51,8 @@
 Valid \CppXX{} code that uses a comma expression within a
 subscript expression may fail to compile. For example:
 \begin{codeblock}
-arr[1, 2]               // was equivalent to \tcode{arr[(1, 2)]}, now equivalent to \tcode{arr.\keyword{operator}[](1, 2)} or ill-formed
+arr[1, 2]               // was equivalent to \tcode{arr[(1, 2)]},
+                        // now equivalent to \tcode{arr.operator[](1, 2)} or ill-formed
 \end{codeblock}
 
 \rSec2[diff.cpp20.utilities]{\ref{utilities}: general utilities library}

source/expressions.tex

@@ -2948,7 +2948,7 @@
 \pnum
 \indextext{operator!subscripting}%
 \indextext{\idxcode{[]}|see{operator, subscripting}}%
-A subscript expression is a postfix expression
+A \defnadj{subscript}{expression} is a postfix expression
 followed by square brackets containing
 a possibly empty, comma-separated list of \grammarterm{initializer-clause}s
 which constitute the arguments to the subscript operator.