Traits

parser/src/grammar.pest

@@ -259,6 +259,24 @@ impl_decl = {
     "impl" ~ generics? ~ type_expr ~ "{" ~ method* ~ "}"
 }
 
+// ======================================================
+// Traits
+// ======================================================
+trait_requirements = { ":" ~ type_expr_param ~ ("+" ~ type_expr_param)* }
+
+method_no_body = {
+    export? ~ type_expr ~ identifier ~ generics? ~ "(" ~ self_param? ~ ("," ~ param_list?)? ~ ")"
+}
+
+trait_item = _{
+    method
+  | method_no_body
+}
+
+trait_decl = {
+    export? ~ "trait" ~ identifier ~ generics? ~ trait_requirements? ~ "{" ~ trait_item* ~ "}"
+}
+
 // ======================================================
 // FUNCTIONS
 // ======================================================
@@ -272,7 +290,7 @@ function_decl = {
 // ======================================================
 
 top_level = {
-    (attributes ~ (import | impl_for_decl | impl_decl | function_decl | struct_decl | enum_decl | class_decl | mod_package))
+    (attributes ~ (import | impl_for_decl | impl_decl | trait_decl | struct_decl | enum_decl | class_decl | mod_package | function_decl))
   | mod_attribute
 }