Merge branch 'incoming'

diff --cc src/libcore/core.rc
index 5997c1d063216102576120ee509fce2c4c5ad290,cfeda40641170b5f7483acb69b14e8be6895e335..f1ceeff9ea809a7d9a217506ccf3f94cac914bfd
--- 1/src/libcore/core.rc
--- 2/src/libcore/core.rc
+++ b/src/libcore/core.rc
@@@ -43,8 -43,10 +43,9 @@@ export comm, task, future
  export extfmt;
  export tuple;
  export to_str;
 -export swappable;
  export dvec, dvec_iter;
  export cmp;
+ export num;
  
  // NDM seems to be necessary for resolve to work
  export option_iter;