diff --git a/devito/mpatches/.__init__.py.swp b/devito/mpatches/.__init__.py.swp
deleted file mode 100644
index 48f848b3e8..0000000000
Binary files a/devito/mpatches/.__init__.py.swp and /dev/null differ
diff --git a/devito/mpatches/.rationaltools.py.swp b/devito/mpatches/.rationaltools.py.swp
deleted file mode 100644
index dcf601c091..0000000000
Binary files a/devito/mpatches/.rationaltools.py.swp and /dev/null differ
diff --git a/devito/types/basic.py b/devito/types/basic.py
index 51dbba181e..d7a422b39e 100644
--- a/devito/types/basic.py
+++ b/devito/types/basic.py
@@ -6,6 +6,7 @@
 
 import numpy as np
 import sympy
+
 from sympy.core.assumptions import _assume_rules
 from cached_property import cached_property
 
@@ -855,11 +856,14 @@ def __str__(self):
 
     __repr__ = __str__
 
-    def _sympystr(self, printer):
+    def _sympystr(self, printer, **kwargs):
         return str(self)
 
     _latex = _sympystr
 
+    def _pretty(self, printer, **kwargs):
+        return printer._print_Function(self, func_name=self.name)
+
     def __eq__(self, other):
         try:
             return (self.function is other.function and
diff --git a/devito/types/dense.py b/devito/types/dense.py
index 19f6aa4769..aec69bc1eb 100644
--- a/devito/types/dense.py
+++ b/devito/types/dense.py
@@ -57,7 +57,7 @@ class DiscreteFunction(AbstractFunction, ArgProvider, Differentiable):
     The type of the underlying data object.
     """
 
-    __rkwargs__ = AbstractFunction.__rkwargs__ + ('staggered',)
+    __rkwargs__ = AbstractFunction.__rkwargs__ + ('staggered', 'coefficients')
 
     def __init_finalize__(self, *args, function=None, **kwargs):
         # Staggering metadata