Author: lwall
Date: 2010-02-03 02:09:04 +0100 (Wed, 03 Feb 2010)
New Revision: 29624
Modified:
docs/Perl6/Spec/S07-iterators.pod
Log:
[S07] @@ squashing
Modified: docs/Perl6/Spec/S07-iterators.pod
===================================================================
--- docs/Perl6/Spec/S07-iterators.pod 2010-02-03 00:47:37 UTC (rev 29623)
+++ docs/Perl6/Spec/S07-iterators.pod 2010-02-03 01:09:04 UTC (rev 29624)
@@ -222,6 +222,10 @@
No list should ever contain the C<EMPTY> exception, since iterational
control flow should always terminate when that value is returned.
+Note: C<get> and C<getobj> must be atomic for any iterator shared
+by more than one thread, since it is likely that message passing is
+implemented in terms of them.
+
=head2 method batchobj ($max?) {...}
Returns a batch of parcels/objects in some appropriate C<Positional> type that
@@ -379,25 +383,34 @@
=head2 Generic Lazy Slice
-The generic lazy slice consumes the C<Capture>s from an iterator but
+The generic lazy slice consumes the C<Parcel>s from an iterator but
stores the results as a bi-dimensional list, where the first dimension
corresponds to an iteration, and the second contains the values in
the C<Parcel> returned for that iteration, but turned into a C<Seq> object.
Empty C<Parcel> objects are turned into empty C<Seq> objects.
+Any other object is returned as itself.
-To obtain a generic lazy slice, end a feed in a sliced C<Positional>.
+To obtain a generic lazy slice, end a feed in a sliced binding.
- my @@it <== map { ... }, 1,2,3;
+ my *...@it <== map { ... }, 1,2,3;
-(XXX TODO:
+Note that in:
- @@it <== (1,mysub(),2;1,2,3);
- @@it[0];
- @@it[0;1];
+ my *...@it <== (1,mysub(),2; 1..*);
- exactly when does mysub() get called?)
+the slice lists are independently lazy. However, the call to
+C<mysub()> is not particularly lazy; it occurs when the parcel is
+constructed. Any laziness is in the function's return value, not in
+the call. A call in the top level of any parcel is called eagerly.
+To call a function lazily it is necessary to embed the call in some
+other explicitly lazy operator:
+ 1, (() ... { START mysub() }), 2 # harder way
+ 1, lazy { mysub() }, 2 # easier way
+[Note: the above text really belongs somewhere else, but I'm too lazy to
+figure out where.]
+
=head1 Coroutines
Perl6 does not have a formally defined sub-style coroutine. Doubtless
