diff --git a/src/protocol/parser/visitor.rs b/src/protocol/parser/visitor.rs
index 02bfaf21b5242a657c1421a777248e2844de5e29..a4794193bcf81b3fdd9a2a30e9f94a4e9d956c33 100644
--- a/src/protocol/parser/visitor.rs
+++ b/src/protocol/parser/visitor.rs
@@ -11,6 +11,9 @@ pub(crate) const STMT_BUFFER_INIT_CAPACITY: usize = 256;
 /// Globally configured vector capacity for expression buffers in visitor
 /// implementations
 pub(crate) const EXPR_BUFFER_INIT_CAPACITY: usize = 256;
+/// Globally configured vector capacity for parser type buffers in visitor
+/// implementations
+pub(crate) const TYPE_BUFFER_INIT_CAPACITY: usize = 128;
 
 /// General context structure that is used while traversing the AST.
 pub(crate) struct Ctx<'p> {
@@ -235,4 +238,7 @@ pub(crate) trait Visitor2 {
     fn visit_constant_expr(&mut self, _ctx: &mut Ctx, _id: ConstantExpressionId) -> VisitorResult { Ok(()) }
     fn visit_call_expr(&mut self, _ctx: &mut Ctx, _id: CallExpressionId) -> VisitorResult { Ok(()) }
     fn visit_variable_expr(&mut self, _ctx: &mut Ctx, _id: VariableExpressionId) -> VisitorResult { Ok(()) }
+
+    // Types
+    fn visit_parser_type(&mut self, _ctx: &mut Ctx, _id: ParserTypeId) -> VisitorResult { Ok(()) }
 }
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