Fix comment

velox/docs/functions/spark/string.rst

@@ -24,9 +24,9 @@ Unless specified otherwise, all functions return NULL if at least one of the arg
 
    Returns the concatenation for ``string`` and all elements in ``array<string>``, separated
    by ``separator``. The type of ``separator`` is VARCHAR . It can take variable number of
-   remaining arguments, where ``string`` & ``array<string>`` can be used in combination. NULL
+   remaining arguments, where ``string`` and ``array<string>`` can be used in combination. NULL
    element is skipped in the concatenation. If ``separator`` is NULL, returns NULL, regardless
-   of the followinginputs. For non-NULL ``separator``, if no remaining input or all remaining
+   of the following inputs. For non-NULL ``separator``, if no remaining input or all remaining
    inputs are NULL, returns an empty string. ::
 
         SELECT concat_ws('~', 'a', 'b', 'c'); -- 'a~b~c'

velox/functions/sparksql/String.cpp

@@ -432,7 +432,7 @@ std::vector<std::shared_ptr<exec::FunctionSignature>> concatWsSignatures() {
           // varchar, [varchar], [array(varchar)], ... -> varchar.
           exec::FunctionSignatureBuilder()
               .returnType("varchar")
-              .constantArgumentType("varchar")
+              .argumentType("varchar")
               .argumentType("any")
               .variableArity()
               .build()};
@@ -457,11 +457,11 @@ std::shared_ptr<exec::VectorFunction> makeConcatWs(
         arg.type->toString());
   }
 
-  BaseVector* constantPattern = inputArgs[0].constantValue.get();
+  BaseVector* constantSeparator = inputArgs[0].constantValue.get();
   std::optional<std::string> separator = std::nullopt;
-  if (constantPattern != nullptr) {
+  if (constantSeparator != nullptr) {
     separator =
-        constantPattern->as<ConstantVector<StringView>>()->valueAt(0).str();
+        constantSeparator->as<ConstantVector<StringView>>()->valueAt(0).str();
   }
 
   return std::make_shared<ConcatWs>(separator);