diff --git a/parser/enum.go b/parser/enum.go
index 80577a7..228c9f0 100644
--- a/parser/enum.go
+++ b/parser/enum.go
@@ -4,6 +4,7 @@ import "git.tebibyte.media/arf/arf/types"
 import "git.tebibyte.media/arf/arf/lexer"
 import "git.tebibyte.media/arf/arf/infoerr"
 
+// parseEnumSection parses an enumerated type section.
 func (parser *ParsingOperation) parseEnumSection () (
 	section *EnumSection,
 	err     error,
diff --git a/parser/node-traits.go b/parser/node-traits.go
index d0e2df0..29e64ce 100644
--- a/parser/node-traits.go
+++ b/parser/node-traits.go
@@ -1,6 +1,7 @@
 package parser
 
 import "git.tebibyte.media/arf/arf/file"
+import "git.tebibyte.media/arf/arf/types"
 import "git.tebibyte.media/arf/arf/infoerr"
 
 // locatable allows a tree node to have a location.
@@ -21,7 +22,8 @@ func (trait locatable) NewError (
 ) (
 	err infoerr.Error,
 ) {
-	return infoerr.NewError(trait.location, message, kind)
+	err = infoerr.NewError(trait.location, message, kind)
+	return
 }
 
 // nameable allows a tree node to have a name.
@@ -41,5 +43,16 @@ type typeable struct {
 
 // Type returns the type of the node.
 func (trait typeable) Type () (what Type) {
-	return trait.what
+	what =  trait.what
+	return
+}
+
+// permissionable allows a node to have a permission.
+type permissionable struct {
+	permission types.Permission
+}
+
+func (trait permissionable) Permission () (permission types.Permission) {
+	permission = trait.permission
+	return
 }
diff --git a/parser/tree.go b/parser/tree.go
index bf99c55..d726cbf 100644
--- a/parser/tree.go
+++ b/parser/tree.go
@@ -1,7 +1,6 @@
 package parser
 
 import "git.tebibyte.media/arf/arf/file"
-import "git.tebibyte.media/arf/arf/types"
 
 // SyntaxTree represents an abstract syntax tree. It covers an entire module. It
 // can be expected to be syntactically correct, but it might not be semantically
@@ -151,9 +150,9 @@ type DataSection struct {
 	locatable
 	nameable
 	typeable
+	permissionable
 	
-	permission types.Permission
-	value      Argument
+	value Argument
 }
 
 // TypeSection represents a blind type definition.
@@ -161,8 +160,8 @@ type TypeSection struct {
 	locatable
 	nameable
 	typeable
+	permissionable
 	
-	permission   types.Permission
 	defaultValue Argument
 }
 
@@ -171,9 +170,9 @@ type ObjtMember struct {
 	locatable
 	nameable
 	typeable
+	permissionable
 	
 	bitWidth     uint64
-	permission   types.Permission
 	defaultValue Argument
 }
 
@@ -181,9 +180,9 @@ type ObjtMember struct {
 type ObjtSection struct {
 	locatable
 	nameable
+	permissionable
 	inherits Identifier
 
-	permission   types.Permission
 	members      []ObjtMember
 }
 
@@ -199,9 +198,9 @@ type EnumSection struct {
 	locatable
 	nameable
 	typeable
+	permissionable
 
-	permission types.Permission
-	members    []EnumMember
+	members []EnumMember
 }
 
 // FaceBehavior represents a behavior of an interface section.
@@ -217,9 +216,9 @@ type FaceBehavior struct {
 type FaceSection struct {
 	locatable
 	nameable
+	permissionable
 	inherits Identifier
 	
-	permission types.Permission
 	behaviors  map[string] FaceBehavior
 }
 
@@ -270,7 +269,7 @@ type FuncOutput struct {
 type FuncSection struct {
 	locatable
 	nameable
-	permission types.Permission
+	permissionable
 	
 	receiver *Declaration
 	inputs   []Declaration
diff --git a/parser/type.go b/parser/type.go
index cacc3b0..5c484f2 100644
--- a/parser/type.go
+++ b/parser/type.go
@@ -2,7 +2,6 @@ package parser
 
 import "git.tebibyte.media/arf/arf/types"
 import "git.tebibyte.media/arf/arf/lexer"
-// import "git.tebibyte.media/arf/arf/infoerr"
 
 // parseTypeSection parses a blind type definition, meaning it can inherit from
 // anything including primitives, but cannot define structure.