diff --git a/vyper/semantics/analysis/pre_typecheck.py b/vyper/semantics/analysis/pre_typecheck.py
index b0e900a76c..cb73271aa6 100644
--- a/vyper/semantics/analysis/pre_typecheck.py
+++ b/vyper/semantics/analysis/pre_typecheck.py
@@ -2,7 +2,36 @@
 from vyper.exceptions import UnfoldableNode
 
 
-def get_constants(node: vy_ast.Module) -> dict:
+def _prefold(node: vy_ast.VyperNode, constants: dict[str, vy_ast.VyperNode]):
+    if isinstance(node, vy_ast.Name):
+        var_name = node.id
+        if var_name in constants:
+            node._metadata["folded_value"] = constants[var_name]
+            return
+
+    if isinstance(node, vy_ast.Call):
+        if isinstance(node.func, vy_ast.Name):
+            from vyper.builtins.functions import DISPATCH_TABLE
+
+            func_name = node.func.id
+
+            call_type = DISPATCH_TABLE.get(func_name)
+            if call_type and hasattr(call_type, "fold"):
+                try:
+                    node._metadata["folded_value"] = call_type.fold(node)
+                    return
+                except UnfoldableNode:
+                    pass
+
+    # call `get_folded_value` for its side effects and allow all
+    # exceptions other than `UnfoldableNode` to raise
+    try:
+        node.get_folded_value()
+    except UnfoldableNode:
+        pass
+
+
+def _get_constants(node: vy_ast.Module) -> dict:
     constants: dict[str, vy_ast.VyperNode] = {}
     module_nodes = node.body.copy()
     const_var_decls = [
@@ -19,18 +48,18 @@ def get_constants(node: vy_ast.Module) -> dict:
                 continue
 
             for n in c.value.get_descendants(include_self=True, reverse=True):
-                prefold(n, constants)
+                _prefold(n, constants)
 
             try:
                 val = c.value.get_folded_value()
-
-                # note that if a constant is redefined, its value will be overwritten,
-                # but it is okay because the syntax error is handled downstream
-                constants[name] = val
-                n_processed += 1
-                const_var_decls.remove(c)
             except UnfoldableNode:
-                pass
+                continue
+            
+            # note that if a constant is redefined, its value will be overwritten,
+            # but it is okay because the syntax error is handled downstream
+            constants[name] = val
+            n_processed += 1
+            const_var_decls.remove(c)
 
         if not n_processed:
             break
@@ -39,39 +68,10 @@ def get_constants(node: vy_ast.Module) -> dict:
 
 
 def pre_typecheck(node: vy_ast.Module) -> None:
-    constants = get_constants(node)
+    constants = _get_constants(node)
 
     for n in node.get_descendants(reverse=True):
         if isinstance(n, vy_ast.VariableDecl):
             continue
 
-        prefold(n, constants)
-
-
-def prefold(node: vy_ast.VyperNode, constants: dict[str, vy_ast.VyperNode]):
-    if isinstance(node, vy_ast.Name):
-        var_name = node.id
-        if var_name in constants:
-            node._metadata["folded_value"] = constants[var_name]
-            return
-
-    if isinstance(node, vy_ast.Call):
-        if isinstance(node.func, vy_ast.Name):
-            from vyper.builtins.functions import DISPATCH_TABLE
-
-            func_name = node.func.id
-
-            call_type = DISPATCH_TABLE.get(func_name)
-            if call_type and hasattr(call_type, "fold"):
-                try:
-                    node._metadata["folded_value"] = call_type.fold(node)
-                    return
-                except UnfoldableNode:
-                    pass
-
-    # call `get_folded_value` for its side effects and allow all
-    # exceptions other than `UnfoldableNode` to raise
-    try:
-        node.get_folded_value()
-    except UnfoldableNode:
-        pass
+        _prefold(n, constants)