Fix setbagmix (#4633)

* Add missing ASCII examples for the Unicode Set, Bag, and Mix operators

+ addresses doc issue #4629

Author: tbrowder

doc/Language/setbagmix.rakudoc

@@ -89,7 +89,8 @@ L<Set Theory|https://en.wikipedia.org/wiki/Set_theory>.
 
 These infixes can be written using the Unicode character that represents the
 function (like C<∈> or C<∪>), or with an equivalent ASCII version (like
-C<(elem)> or C<(|)>).
+C<(elem)> or C<(|)>). Prefix the ASCII version with C<!> to negate it
+(like C<!(elem)> or C<!(|)>).
 
 So explicitly using L<C<Set>|/type/Set> (or L<C<Bag>|/type/Bag> or L<C<Mix>|/type/Mix>) objects with these infixes is
 unnecessary.  All set operators work with all possible arguments, including
@@ -108,7 +109,7 @@ Returns C<True> if C<$a> is an B<element> of C<$b>, else C<False>.
 L<More information|/language/operators#infix_(elem),_infix_∈>,
 L<Wikipedia definition|https://en.wikipedia.org/wiki/Element_(mathematics)#Notation_and_terminology>.
 
-=head3 infix ∉
+=head3 infix !(elem), infix ∉
 
 Returns C<True> if C<$a> is B<not> an element of C<$b>, else C<False>.
 L<More information|/language/operators#infix_∉>,
@@ -120,7 +121,7 @@ Returns C<True> if C<$a> B<contains> C<$b> as an element, else C<False>.
 L<More information|/language/operators#infix_(cont),_infix_∋>,
 L<Wikipedia definition|https://en.wikipedia.org/wiki/Element_(mathematics)#Notation_and_terminology>.
 
-=head3 infix ∌
+=head3 infix !(cont), infix ∌
 
 Returns C<True> if C<$a> does B<not> contain C<$b>, else C<False>.
 L<More information|/language/operators#infix_∌>,
@@ -132,7 +133,7 @@ Returns C<True> if C<$a> is a B<subset> or is equal to C<$b>, else C<False>.
 L<<More information|/language/operators#infix_(<=),_infix_⊆>>,
 L<Wikipedia definition|https://en.wikipedia.org/wiki/Subset#Definitions>.
 
-=head3 infix ⊈
+=head3 infix !(<=), infix ⊈
 
 Returns C<True> if C<$a> is B<not> a B<subset> nor equal to C<$b>, else C<False>.
 L<More information|/language/operators#infix_⊈>,
@@ -144,7 +145,7 @@ Returns C<True> if C<$a> is a B<strict subset> of C<$b>, else C<False>.
 L<<More information|/language/operators#infix_(<),_infix_⊂>>,
 L<Wikipedia definition|https://en.wikipedia.org/wiki/Subset#Definitions>.
 
-=head3 infix ⊄
+=head3 infix !(<), infix ⊄
 
 Returns C<True> if C<$a> is B<not> a B<strict subset> of C<$b>, else C<False>.
 L<More information|/language/operators#infix_⊄>,
@@ -156,7 +157,7 @@ Returns C<True> if C<$a> is a B<superset> of or equal to C<$b>, else C<False>.
 L«More information|/language/operators#infix_(>=),_infix_⊇»,
 L<Wikipedia definition|https://en.wikipedia.org/wiki/Subset#Definitions>.
 
-=head3 infix ⊉
+=head3 infix !(>=), infix ⊉
 
 Returns C<True> if C<$a> is B<not> a B<superset> nor equal to C<$b>, else C<False>.
 L<More information|/language/operators#infix_⊉>,
@@ -168,7 +169,7 @@ Returns C<True> if C<$a> is a B<strict superset> of C<$b>, else C<False>.
 L«More information|/language/operators#infix_(>),_infix_⊃»,
 L<Wikipedia definition|https://en.wikipedia.org/wiki/Subset#Definitions>.
 
-=head3 infix ⊅
+=head3 infix !(>), infix ⊅
 
 Returns C<True> if C<$a> is B<not> a B<strict superset> of C<$b>, else C<False>.
 L<More information|/language/operators#infix_⊅>,
@@ -185,7 +186,7 @@ versions of Rakudo can install the
 L<Set::Equality|https://raku.land/zef:lizmat/Set::Equality> module for
 the same functionality.
 
-=head3 infix ≢
+=head3 infix !(==), infix ≢
 
 Returns C<True> if C<$a> and C<$b> are B<not identical>, else C<False>.
 L<More information|/language/operators#infix_≢>,