Can't .take uncached Seq

[zoffixznet]

Don't know if it's a limitation or a bug, but if you try to take an uncached Seq it will end up consumed by the time it gets to the other end:

$ perl6 -e 'dd gather { ().Seq.take }'
(Seq.new-consumed(),).Seq

$ perl6 -e 'use nqp; dd gather { THROW(nqp::const::CONTROL_TAKE, ().Seq) }'
(Seq.new-consumed(),).Seq

$ perl6 -v
This is Rakudo version 2018.03-216-g7b5ccaa built on MoarVM version 2018.03-99-g4234ab5
implementing Perl 6.c.

Originally discovered through ... op's use, which does a .take under the hood.

[zoffixznet]

Doh. It's the sink that kills it:

$ perl6 -e 'dd gather { $ := ().Seq.take }'
(().Seq,).Seq

Gonna patch up SEQUENCE.