Make classes private by default (#759)

compiler/ast.jou

@@ -22,6 +22,7 @@ enum AstTypeKind:
     Array
 
 
+@public
 class AstArrayType:
     member_type: AstType*
     length: AstExpression*
@@ -33,6 +34,7 @@ class AstArrayType:
         free(self->length)
 
 
+@public
 class AstType:
     kind: AstTypeKind
     location: Location
@@ -97,12 +99,14 @@ class TreePrinter:
 
 
 # Foo.Bar where Foo is an enum
+@public
 class AstEnumMember:
     enum_name: byte[100]
     member_name: byte[100]
 
 
 # foo.bar, foo->bar
+@public
 class AstClassField:
     instance: AstExpression*
     uses_arrow_operator: bool  # distinguishes foo.bar and foo->bar
@@ -114,6 +118,7 @@ class AstClassField:
 
 
 # Foo{bar = 1, baz = 2}
+@public
 class AstInstantiation:
     class_name_location: Location  # TODO: probably not necessary, can use location of the instantiate expression
     class_name: byte[100]
@@ -183,6 +188,7 @@ enum AstExpressionKind:
     And         # x and y
     Or          # x or y
 
+@public
 class AstExpression:
     location: Location
     kind: AstExpressionKind
@@ -382,6 +388,7 @@ class AstExpression:
 
 
 # [foo, bar, baz]
+@public
 class AstArray:
     length: int
     items: AstExpression*
@@ -393,6 +400,7 @@ class AstArray:
 
 
 # foo as bar
+@public
 class AstAs:
     value: AstExpression
     type: AstType
@@ -414,6 +422,7 @@ class AstAs:
 # foo(arg1, arg2, arg3)
 # foo.bar(arg1, arg2, arg3)
 # foo->bar(arg1, arg2, arg3)
+@public
 class AstCall:
     location: Location
     name: byte[100]  # name of function or method
@@ -459,6 +468,7 @@ class AstCall:
 
 
 # assert foo
+@public
 class AstAssertion:
     condition: AstExpression
     condition_str: byte*
@@ -498,6 +508,7 @@ enum AstStatementKind:
     GlobalVariableDeclare
     GlobalVariableDef
 
+@public
 class AstStatement:
     location: Location
     kind: AstStatementKind
@@ -657,6 +668,7 @@ class AstStatement:
 
 
 # Useful for e.g. "while condition: body", "if condition: body"
+@public
 class AstConditionAndBody:
     condition: AstExpression
     body: AstBody
@@ -679,6 +691,7 @@ class AstConditionAndBody:
 
 
 # foo = bar
+@public
 class AstAssignment:
     target: AstExpression
     value: AstExpression
@@ -703,6 +716,7 @@ class AstAssignment:
 #     ...
 # else:
 #     ...
+@public
 class AstIfStatement:
     if_and_elifs: AstConditionAndBody*
     n_if_and_elifs: int  # At least 1 (the if statement). The rest, if any, are elifs.
@@ -733,6 +747,7 @@ class AstIfStatement:
 #         ...
 #     case ...:
 #         ...
+@public
 class AstMatchStatement:
     match_obj: AstExpression
     func_name: byte[100]  # empty if there's no "with foo"
@@ -766,6 +781,7 @@ class AstMatchStatement:
 
 # case case_obj1 | case_obj2 | case_obj3:
 #     body
+@public
 class AstCase:
     case_objs: AstExpression*
     n_case_objs: int
@@ -790,6 +806,7 @@ class AstCase:
 
 # for init; cond; incr:
 #     ...body...
+@public
 class AstForLoop:
     init: AstStatement*   # may be NULL
     cond: AstExpression*  # may be NULL
@@ -835,6 +852,7 @@ class AstForLoop:
 
 
 # name: type = value
+@public
 class AstNameTypeValue:
     name: byte[100]
     name_location: Location
@@ -883,6 +901,7 @@ class AstGlobalVarDeclare:
 
 # global foo: int
 # TODO: support specifying an initial value
+@public
 class AstGlobalVarDef:
     name: byte[100]
     type: AstType
@@ -899,6 +918,7 @@ class AstGlobalVarDef:
 
 
 # typically multiple indented lines after a ":" at end of line
+@public
 class AstBody:
     statements: AstStatement*
     nstatements: int
@@ -917,6 +937,7 @@ class AstBody:
 
 
 # function name and parameters in "def" or "declare"
+@public
 class AstSignature:
     name_location: Location
     name: byte[100]  # name of function or method, after "def" keyword
@@ -958,6 +979,7 @@ class AstSignature:
 
 
 # import "./foo.jou"
+@public
 class AstImport:
     specified_path: byte*  # Path in jou code e.g. "stdlib/io.jou"
     resolved_path: byte*  # Absolute path or relative to current working directory e.g. "/home/akuli/jou/stdlib/io.jou"
@@ -975,6 +997,7 @@ class AstImport:
 
 
 # Represents the AST of one Jou file.
+@public
 class AstFile:
     path: byte*  # not owned
     is_main_file: bool  # is this the file passed in Jou compiler command? False means imported file
@@ -993,6 +1016,7 @@ class AstFile:
 
 # def foo() -> bar:
 #     ...
+@public
 class AstFunctionOrMethod:
     ast_signature: AstSignature
     body: AstBody
@@ -1018,6 +1042,7 @@ class AstFunctionOrMethod:
 # union:
 #     foo: type1
 #     bar: type2
+@public
 class AstUnionFields:
     fields: AstNameTypeValue*
     nfields: int
@@ -1038,10 +1063,13 @@ class AstUnionFields:
 
 # class Foo:
 #     ...members...
+@public
 class AstClassDef:
     name: byte[100]
     body: AstBody*
     type: Type*  # populated in typecheck, NULL before typecheck runs
+    public: bool  # is it decorated with @public
+    used: bool  # used to detect unused classes
 
     def print(self) -> None:
         self->print_with_tree_printer(TreePrinter{})
@@ -1059,6 +1087,7 @@ class AstClassDef:
 #     Member1
 #     Member2
 #     Member3
+@public
 class AstEnumDef:
     name: byte[100]
     name_location: Location

compiler/builders/either_builder.jou

@@ -16,16 +16,19 @@ import "./llvm_builder.jou"
 import "./uvg_builder.jou"
 
 
+@public
 class EitherBuilderValue:
     lvalue: LBuilderValue
     uvalue: int
 
 
+@public
 class EitherBuilderBlock:
     lblock: LLVMBasicBlock*
     ublock: UvgBlock*  # funny naming :)
 
 
+@public
 class EitherBuilder:
     lbuilder: LBuilder*  # may be NULL
     ubuilder: UBuilder*  # may be NULL

compiler/builders/llvm_builder.jou

@@ -220,12 +220,14 @@ def find_enum_member(enumtype: Type*, name: byte*) -> int:
     assert False
 
 
+@public
 class LBuilderValue:
     type: Type*
     llvm_value: LLVMValue*
 
 
 # Not named LLVMBuilder because that is the name of LLVM's thing.
+@public
 class LBuilder:
     llvm_module: LLVMModule*
     llvm_builder: LLVMBuilder*

compiler/builders/uvg_builder.jou

@@ -25,6 +25,7 @@ def FALSE_ID() -> int:
     return -3
 
 
+@public
 class UBuilder:
     uvg: Uvg
     current_block: UvgBlock*

compiler/errors_and_warnings.jou

@@ -1,6 +1,7 @@
 import "stdlib/process.jou"
 import "stdlib/io.jou"
 
+@public
 class Location:
     path: byte*  # Not owned. Points to a string that is held elsewhere.
     lineno: int

compiler/llvm.jou

@@ -1,20 +1,28 @@
+@public
 class LLVMModule:
     _dummy: int
+@public
 class LLVMType:
     _dummy: int
+@public
 class LLVMValue:
     _dummy: int
+@public
 class LLVMBasicBlock:
     _dummy: int
+@public
 class LLVMBuilder:
     _dummy: int
 class LLVMPassManager:
     _dummy: int
 
+@public
 class LLVMTarget:
     _dummy: int
+@public
 class LLVMTargetData:
     _dummy: int
+@public
 class LLVMTargetMachine:
     _dummy: int
 

compiler/main.jou

@@ -146,6 +146,10 @@ class FileState:
                     if not stmt->global_var_declare.public and not stmt->global_var_declare.used:
                         snprintf(msg, sizeof msg, "global variable '%s' declared but not used", stmt->global_var_declare.name)
                         show_warning(stmt->location, msg)
+                case AstStatementKind.Class:
+                    if not stmt->classdef.public and not stmt->classdef.used:
+                        snprintf(msg, sizeof msg, "class '%s' defined but not used", stmt->classdef.name)
+                        show_warning(stmt->location, msg)
                 case _:
                     pass
 

compiler/parser.jou

@@ -145,16 +145,16 @@ def decorate(stmt: AstStatement*, decor: byte*, location: Location) -> None:
                 if strcmp(stmt->function.ast_signature.name, "main") == 0:
                     fail(location, "the main() function cannot be @public")
                 stmt->function.public = True
+            case AstStatementKind.MethodDef:
+                fail(location, "methods cannot be decorated with @public, a class is either fully public or fully private")
+            case AstStatementKind.Class:
+                stmt->classdef.public = True
             case AstStatementKind.Enum:
                 stmt->enumdef.public = True
             case AstStatementKind.GlobalVariableDeclare:
                 stmt->global_var_declare.public = True
             case AstStatementKind.GlobalVariableDef:
                 stmt->global_var_def.public = True
-            # Temporarily allow and ignore using @public on enums, classes and global variables.
-            # This is needed for the bootstrap compiler to accept new syntax.
-            case AstStatementKind.Class:
-                pass  # TODO: handle these cases properly
             case _:
                 fail(location, "the @public decorator cannot be used here")
     else:

compiler/token.jou

@@ -25,6 +25,7 @@ enum TokenKind:
     Operator
     EndOfFile  # Marks the end of an array of tokens.
 
+@public
 class Token:
     kind: TokenKind
     location: Location

compiler/typecheck/common.jou

@@ -18,6 +18,7 @@ enum ExportSymbolKind:
     Type
     GlobalVar
 
+@public
 class ExportSymbol:
     kind: ExportSymbolKind
     name: byte[100]  # TODO: maybe this should be 200 because it can be ClassName.method_name? or something else?

compiler/typecheck/step1_create_types.jou

@@ -29,8 +29,8 @@ def typecheck_step1_create_types(ast: AstFile*) -> ExportSymbol*:
         match stmt->kind:
             case AstStatementKind.Class:
                 name = stmt->classdef.name
-                public = True
-                usedptr = NULL
+                public = stmt->classdef.public
+                usedptr = &stmt->classdef.used
                 t = create_opaque_class(name)
                 stmt->classdef.type = t
             case AstStatementKind.Enum:

compiler/types.jou

@@ -3,6 +3,7 @@ import "stdlib/str.jou"
 
 import "./errors_and_warnings.jou"
 
+@public
 class ClassField:
     name: byte[100]
     type: Type*
@@ -37,6 +38,7 @@ enum TypeKind:
     OpaqueClass  # class with unknown members, used temporarily during type checking
     Enum
 
+@public
 class Type:
     name: byte[500]   # All types have a name for error messages and debugging.
     kind: TypeKind
@@ -283,6 +285,7 @@ def create_enum(name: byte*, membercount: int, membernames: byte[100]*) -> Type*
     return &result->type
 
 
+@public
 class Signature:
     name: byte[100]  # Function or method name. For methods it does not include the name of the class.
     nargs: int