Make array variable names consistent

presto-docs/src/main/sphinx/functions/array.rst

@@ -29,9 +29,9 @@ Array Functions
 
  Returns an array of the elements in the intersection of ``x`` and ``y``, without duplicates.
 
-.. function:: array_position(array, element) -> bigint
+.. function:: array_position(x, element) -> bigint
 
- Returns the position of the first occurrence of the ``element`` in ``array`` (or 0 if not found).
+ Returns the position of the first occurrence of the ``element`` in array ``x`` (or 0 if not found).
 
 .. function:: array_sort(x) -> array
 
@@ -47,9 +47,9 @@ Array Functions
  Concatenates the arrays ``x`` and ``y``. This function provides the same
  functionality as the SQL-standard concatenation operator (``||``).
 
-.. function:: contains(array, element) -> boolean
+.. function:: contains(x, element) -> boolean
 
- Returns true if the ``array`` contains the ``element``.
+ Returns true if the array ``x`` contains the ``element``.
 
 .. function:: array_join(x, delimiter, null_replacement) -> varchar