more about identifier terms

lib/terms.pod

@@ -95,6 +95,17 @@ TODO
 
 =head1 Identifier terms
 
+There are built-in identifier terms in Perl 6, which are listed below.
+In addition one can add new identifier terms with the syntax
+
+    sub term:<fourty-two> { 42 };
+    say fourty-two
+
+or as constants
+
+    constant forty-two = 42;
+    say fourty-two
+
 =head2 self
 
 Inside a method, C<self> refers to the invocant (i.e. the object the method
@@ -109,4 +120,21 @@ Returns an L<Instant> object representing the current time.
 
 Returns a pseudo-random L<Num> in the range C<0..^1>.
 
+=head2 pi
+
+Returns the number C<pi>, i.e. the ratio between circumference and diameter of
+a circle.
+
+=head2 e
+
+Returns Euler's number
+
+=head2 i
+
+Returns the imaginary unit (for L<Complex> numbers).
+
+=head1 Variables
+
+Variables are discussed in L<variable language docs |/language/variables>.
+
 =end pod