diff --git a/jedi/evaluate_representation.py b/jedi/evaluate_representation.py
index aa19b894..dfb62057 100644
--- a/jedi/evaluate_representation.py
+++ b/jedi/evaluate_representation.py
@@ -812,9 +812,12 @@ class Array(use_metaclass(cache.CachedMetaClass, pr.Base)):
                 # otherwise it just ignores the index (e.g. [1+1]).
                 index = index_possibilities[0]
                 if isinstance(index, Instance) \
-                    and str(index.name) in ['int', 'str'] \
+                        and str(index.name) in ['int', 'str'] \
                         and len(index.var_args) == 1:
-                    with common.ignored(KeyError, IndexError):
+                    # TODO this is just very hackish and a lot of use cases are
+                    # being ignored
+                    with common.ignored(KeyError, IndexError,
+                                        UnboundLocalError, TypeError):
                         return self.get_exact_index_types(index.var_args[0])
 
         result = list(self._follow_values(self._array.values))
diff --git a/test/completion/arrays.py b/test/completion/arrays.py
index 4725435d..26d20950 100644
--- a/test/completion/arrays.py
+++ b/test/completion/arrays.py
@@ -11,6 +11,8 @@
 [1,""][2]
 #? int() str()
 [1,""][20]
+#? int() str()
+[1,""][str(hello)]
 
 a = list()
 #? list()
@@ -215,6 +217,11 @@ def y(a):
 #? 
 y(**d)
 
+# problem with more complicated casts
+dic = {str(key): ''}
+#? str()
+dic['']
+
 # -----------------
 # with variable as index
 # -----------------