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diff --git a/pod/perlsub.pod b/pod/perlsub.pod
index 969d0ba..3619014 100644
--- a/pod/perlsub.pod
+++ b/pod/perlsub.pod
@@ -588,6 +588,8 @@ separator.
 Notably, if you want to work with a brand new value of the default scalar
 $_, and avoid the potential problem listed above about $_ previously
 carrying a magic value, you should use C<local *_> instead of C<local $_>.
+As of perl 5.9.1, you can also use the lexical form of C<$_> (declaring it
+with C<my $_>), which avoids completely this problem.
 
 =head3 Localization of elements of composite types
 
@@ -1131,7 +1133,17 @@ The following functions would all be inlined:
     sub FLAG_MASK ()	{ FLAG_FOO | FLAG_BAR }
 
     sub OPT_BAZ ()	{ not (0x1B58 & FLAG_MASK) }
-    sub BAZ_VAL () {
+
+    sub N () { int(OPT_BAZ) / 3 }
+
+    sub FOO_SET () { 1 if FLAG_MASK & FLAG_FOO }
+
+Be aware that these will not be inlined; as they contain inner scopes,
+the constant folding doesn't reduce them to a single constant:
+
+    sub foo_set () { if (FLAG_MASK & FLAG_FOO) { 1 } }
+
+    sub baz_val () {
 	if (OPT_BAZ) {
 	    return 23;
 	}
@@ -1140,13 +1152,6 @@ The following functions would all be inlined:
 	}
     }
 
-    sub N () { int(BAZ_VAL) / 3 }
-    BEGIN {
-	my $prod = 1;
-	for (1..N) { $prod *= $_ }
-	sub N_FACTORIAL () { $prod }
-    }
-
 If you redefine a subroutine that was eligible for inlining, you'll get
 a mandatory warning.  (You can use this warning to tell whether or not a
 particular subroutine is considered constant.)  The warning is