compiler: Relax ComponentAccess

Author: FabioLuporini

devito/passes/iet/languages/CIR.py

@@ -8,4 +8,9 @@ class CIRPrinter(CPrinter):
     """
 
     def _print_ComponentAccess(self, expr):
-        return f"{self._print(expr.base)}.<{expr.sindex},{expr.function.ncomp}>"
+        try:
+            ncomp = expr.function.ncomp
+        except AttributeError:
+            # E.g., the argument is a plain Symbol
+            ncomp = 'N'
+        return f"{self._print(expr.base)}.<{expr.sindex},{ncomp}>"

devito/types/array.py

@@ -588,8 +588,9 @@ class ComponentAccess(Expr, Pickable):
     __rkwargs__ = ('index',)
 
     def __new__(cls, arg, index=0, **kwargs):
-        if not arg.is_Indexed:
-            raise ValueError("Expected Indexed, got `%s` instead" % type(arg))
+        if not (arg.is_Symbol or arg.is_Indexed):
+            raise ValueError(f"Expected Symbol or Indexed, got `{type(arg)}` "
+                             "instead")
         if not is_integer(index) or index > 3:
             raise ValueError("Expected 0 <= index < 4")