diff --git a/core.go b/core.go
index 835739f..cb1c948 100644
--- a/core.go
+++ b/core.go
@@ -2,41 +2,29 @@
 
 package xodr
 
-type EDataQualityRawDataPostProcessing struct {
-}
+type EDataQualityRawDataPostProcessing string
 
-type EDataQualityRawDataSource struct {
-}
+type EDataQualityRawDataSource string
 
-type EUnit struct {
-}
+type EUnit any
 
-type EUnitDistance struct {
-}
+type EUnitDistance string
 
-type EUnitMass struct {
-}
+type EUnitMass string
 
-type EUnitSlope struct {
-}
+type EUnitSlope string
 
-type EUnitSpeed struct {
-}
+type EUnitSpeed string
 
-type GrEqZero struct {
-}
+type GrEqZero float64
 
-type GrEqZeroOrContactPoint struct {
-}
+type GrEqZeroOrContactPoint any
 
-type GrZero struct {
-}
+type GrZero float64
 
-type YesNo struct {
-}
+type YesNo string
 
-type ZeroOne struct {
-}
+type ZeroOne float64
 
 // TODO: Doc formatting needs to be implemented!
 type OpenDriveElement struct {
diff --git a/templates/core.tmpl b/templates/core.tmpl
index c1fe4ef..62d4a23 100644
--- a/templates/core.tmpl
+++ b/templates/core.tmpl
@@ -3,8 +3,7 @@
 package xodr
 
 {{range .SimpleType}}
-    type {{ goType .Name }} struct {
-    }
+    type {{ goType .Name }} {{if .Restriction.Base}} {{ goType .Restriction.Base }} {{else}} any {{end}}
 {{end}}
 
 {{range .ComplexType}}