Any.first edited, with some explanations added. Closes #2877

Author: JJ

doc/Type/Any.pod6

@@ -777,11 +777,11 @@ In general, coerces the invocant to a C<list> by applying its
 L«C<.list>|/routine/list» method and uses
 L«C<List.first>|/type/List#routine_first» on it.
 
-However, there are several different methods, and they have (slightly) different
-behavior. Using a C<Bool> as the argument will always return a L<Failure>. Using
-it as a subroutine is equivalent to using it as a method with the second
-argument as the object.
+However, this is a multi with different signatures, which are implemented with
+(slightly) different behavior, although using it as a subroutine is equivalent
+to using it as a method with the second argument as the object.
 
+For starters, using a C<Bool> as the argument will always return a L<Failure>.
 The form that uses a C<$test> will return the first element that smartmatches
 it, starting from the end if C<:end> is used.
 
@@ -791,19 +791,23 @@ it, starting from the end if C<:end> is used.
     say first 0xF, (⅓,⅔…30);     # OUTPUT: «15␤»
     say (3..33).first( /\d\d/ ); # OUTPUT: «10␤»
 
-The third and fourth example use the C<Mu $test> forms which smartmatches and
+The third and fourth examples use the C<Mu $test> forms which smartmatches and
 returns the first element that does. The last example uses as a test a regex for
 numbers with two figures, and thus the first that meets that criterion is number
 10. This last form uses the C<Callable> multi:
 
     say (⅓,⅔…30).first( * %% 11, :end, :kv ); # OUTPUT: «(65 22)␤»
 
+Besides, the search for first will start from the C<:end> and returns the set of
+key/values in a list; the I<key> in this case is simply the position it occupies
+in the C<Seq>. The C<:kv> argument, which is part of the C<%a> argument in the
+definitions above, modifies what C<first> returns, providing it as a flattened list of keys and values; for a listy object, the key will always be the index.
+
 From version 6.d, the test can also be a C<Junction>:
 
     say (⅓,⅔…30).first( 3 | 33, :kv ); # OUTPUT: «(8 3)␤»
 
-Besides, starts from the C<:end> and returns the C<:kv> in a list; the I<key> in
-this case is simply the position it occupies in the C<Seq>.
+
 
 =head2 method unique