fix signatures for array_append, array_prepend, and aliases

Author: Michael-J-Ward

src/functions.rs

@@ -562,10 +562,10 @@ expr_fn!(arrow_typeof);
 scalar_function!(random, Random);
 
 // Array Functions
-array_fn!(array_append, array elem);
-array_fn!(array_push_back, array_prepend, array elem);
-array_fn!(list_append, array_append, array elem);
-array_fn!(list_push_back, array_append, array elem);
+array_fn!(array_append, array element);
+array_fn!(array_push_back, array_append, array element);
+array_fn!(list_append, array_append, array element);
+array_fn!(list_push_back, array_append, array element);
 array_fn!(array_dims, array);
 array_fn!(array_distinct, array);
 array_fn!(list_distinct, array_distinct, array);
@@ -583,10 +583,10 @@ array_fn!(array_positions, array_positions, array element);
 array_fn!(list_positions, array_positions, array element);
 array_fn!(array_ndims, array);
 array_fn!(list_ndims, array_ndims, array);
-array_fn!(array_prepend, array element);
-array_fn!(array_push_front, array_prepend, array element);
-array_fn!(list_prepend, array_prepend, array element);
-array_fn!(list_push_front, array_prepend, array element);
+array_fn!(array_prepend, element array);
+array_fn!(array_push_front, array_prepend, element array);
+array_fn!(list_prepend, array_prepend, element array);
+array_fn!(list_push_front, array_prepend, element array);
 array_fn!(array_pop_back, array);
 array_fn!(array_pop_front, array);
 array_fn!(array_remove, array element);