# HG changeset patch
# User Colin Macdonald <cbm@m.fsf.org>
# Date 1469480657 25200
# Node ID decd3bd7da7e57def065a34f8f38d8111984cddb
# Parent  c8da556b679321ae06f51d0d91a0d04b66310d72
Partial support for multiple outputs from callables

* @pyobject/subsref.m: Multiple ouputs.

diff -r c8da556b6793 -r decd3bd7da7e @pyobject/subsref.m
--- a/@pyobject/subsref.m	Wed Jul 27 20:30:35 2016 -0700
+++ b/@pyobject/subsref.m	Mon Jul 25 14:04:17 2016 -0700
@@ -75,8 +75,14 @@
 
   ## unpack results, ensure "ans" works (see also pycall)
   is_none = pyeval ("lambda x: x is None");
-  if (nargout > 0 || ! pycall (is_none, r))
+  if (nargout == 0 && ! pycall (is_none, r))
+    varargout{1} = r;
+  elseif (nargout == 1)
     varargout{1} = r;
+  elseif (nargout >= 2)
+    assert (length (r) == nargout, ...
+            "pyobject/subsref: number of outputs must match")
+    [varargout{1:nargout}] = r{1:nargout};
   endif
 endfunction
 
@@ -177,3 +183,33 @@
 %! s.pop ();
 %! assert (exist ("ans", "var"))
 %! assert (length (s) == 1)
+
+%!test
+%! % multiple return values: can get all of them
+%! f = pyeval ("lambda: (1, 2, 3)");
+%! a = f ();
+%! assert (length (a) == 3)
+
+%!test
+%! % multiple return values: separate them
+%! f = pyeval ("lambda: (1, 2, 3)");
+%! [a, b, c] = f ();
+%! assert (a, 1)
+%! assert (b, 2)
+%! assert (c, 3)
+
+%!test
+%! % multiple return values: set ans
+%! f = pyeval ("lambda: (1, 2, 3)");
+%! f ();
+%! assert (length (ans) == 3)
+
+%!error <outputs must match>
+%! % multiple return values: too many outputs
+%! f = pyeval ("lambda: (1, 2)");
+%! [a, b, c] = f ();
+
+%!error <outputs must match>
+%! % multiple return values: not enough outputs
+%! f = pyeval ("lambda: (1, 2, 3)");
+%! [a, b] = f ();