добавил декларацию интерфейсов

analyzers/test/test.l

@@ -73,6 +73,7 @@ LETTER_OR_DIGIT        [a-zA-Z0-9_]
 "++"                   { return INC; }
 "--"                   { return DEC; }
 
+"interface"            { return INTERFACE; }
 "map"                  { return MAP; }
 "struct"               { return STRUCT; }
 "type"                 { return TYPE; }

analyzers/test/test.y

@@ -25,7 +25,7 @@ void free_node(char *str) {
 %token VAR FUNC RETURN STRING_LITERAL FLOAT_LITERAL COMPLEX_LITERAL NUMBER PACKAGE IMPORT
 %token INC DEC PLUS_EQ MINUS_EQ MUL_EQ DIV_EQ MOD_EQ
 %token AMPERSAND_EQ PIPE_EQ XOR_EQ LSHIFT_EQ RSHIFT_EQ AND_NOT_EQ
-%token FOR BREAK CONTINUE ARROW IF ELSE RANGE DEFER GO TYPE STRUCT MAP CHAN
+%token FOR BREAK CONTINUE ARROW IF ELSE RANGE DEFER GO TYPE STRUCT MAP CHAN INTERFACE
 %token CHAN CONST CASE SWITCH MAKE
 %token PLUS MINUS MULT DIV MOD
 %token STRING
@@ -271,6 +271,9 @@ log_expr:
 
 // types
 
+interface_types:
+    INTERFACE {printf("INTERFACE\n"); } LBRACE interface_declarate_field_list RBRACE
+
 struct_types:
     STRUCT LBRACE declarate_field_list RBRACE
     ;
@@ -314,6 +317,7 @@ type:
     | map_types
     | slice_types
     | arr_types {  }
+    | interface_types
     | struct_types {  }
     | func_types {  }
     | string_types {  }
@@ -462,12 +466,22 @@ map_element:
     IDENTIFIER LBRACK literal RBRACK
     | IDENTIFIER LBRACK any_identifier RBRACK
 
+// interface
+
+interface_field:
+    IDENTIFIER LPAREN arg_list RPAREN {printf("ret type interface\n");} return_type
+
+interface_declarate_field_list:
+    | interface_field SEMICOLON
+    | interface_declarate_field_list interface_field SEMICOLON
+    ;
+
 // struct
 declarate_field_list:
-    | arg_declaration
+    | arg_declaration SEMICOLON
-    | IDENTIFIER
+    | IDENTIFIER SEMICOLON
-    | declarate_field_list SEMICOLON arg_declaration
+    | declarate_field_list arg_declaration SEMICOLON
-    | declarate_field_list SEMICOLON IDENTIFIER
+    | declarate_field_list IDENTIFIER SEMICOLON
     ;
 
 field:

tests/test_interfaces.txt

@@ -0,0 +1,6 @@
+package main;
+
+type test interface{
+    a(a int) (a, b int);
+    b() (a, b int, string);
+};

tests/test_methods.txt

@@ -2,7 +2,7 @@ package main;
 
 // Circle - структура, представляющая круг
 type Circle struct {
-    Radius float64
+    Radius float64;
 };
 
 // Реализация методов интерфейса Geometry для Circle

tests/test_types.txt

@@ -15,12 +15,12 @@ type empty struct{
 
 type person struct{
     name string;
-    age int
+    age int;
 };
 type person2 struct{
     name,second_name string;
     age int;
-    person
+    person;
 };