+=head2 C<yield>
+
+ yield;
+ yield @values, $context;
+
+Returns C<@values> I<from> the context pointed by or just above C<$context>, and immediately restart the program flow at this point.
+If C<@values> is empty, then the C<$context> parameter is optional and defaults to the current context ; otherwise it is mandatory.
+
+L</yield> differs from L</unwind> in that it can target I<any> upper scope (besides a C<s///e> substitution context) and not necessarily a sub, an eval or a format.
+Hence you can use it to return values from a C<do> or a C<map> block :
+
+ my $now = do {
+ local $@;
+ eval { require Time::HiRes } or yield time() => HERE;
+ Time::HiRes::time();
+ };
+
+ my @uniq = map {
+ yield if $seen{$_}++; # returns the empty list from the block
+ ...
+ } @things;
+
+Like for L</unwind>, the upper context isn't coerced onto C<@values>.
+
+=head2 C<leave>
+
+ leave;
+ leave @values;
+
+Immediately returns C<@values> from the current block, whatever it may be (besides a C<s///e> substitution context).
+C<leave> is actually a synonym for C<unwind HERE>, while C<leave @values> is a synonym for C<yield @values, HERE>.
+
+=head2 C<want_at>
+
+ my $want = want_at;
+ my $want = want_at $context;