document Cancellation #589

doc/Type/Cancellation.pod

@@ -0,0 +1,31 @@
+=begin pod
+
+=TITLE class Cancellation
+
+=SUBTITLE Removal of a task from a Scheduler before normal completion
+
+    my class Cancellation { ... }
+
+A low level part of the Perl 6 L<concurrency|/language/concurrency#Schedulers>
+system. Some L<Scheduler> objects return a C<Cancellation> with the
+L<.cue|/type/Scheduler#method_cue> method which can be used to cancel the
+scheduled execution before normal completion.  C<Cancellation.cancelled> is a
+boolean that is true after L<#cancel> is called.
+
+=head1 Methods
+
+=head2 method cancel
+
+Defined as:
+
+    method cancel()
+
+Usage:
+
+    CANCELLATION.cancel
+
+Cancels the scheduled execution of a task before normal completion.
+
+=end pod
+
+# vim: expandtab shiftwidth=4 ft=perl6