struct AstNode; struct Type; struct AstScope; enum ParseFileError { ParseFile_None, ParseFile_WrongExtension, ParseFile_InvalidFile, ParseFile_EmptyFile, ParseFile_Permission, ParseFile_NotFound, ParseFile_InvalidToken, ParseFile_Count, }; struct AstFile { gbArena arena; Tokenizer tokenizer; gbArray(Token) tokens; Token * cursor; // NOTE(bill): Current token, easy to peek forward and backwards if needed // >= 0: In Expression // < 0: In Control Clause // NOTE(bill): Used to prevent type literals in control clauses isize expression_level; AstNode *declarations; isize declaration_count; AstScope *file_scope; AstScope *curr_scope; isize scope_level; ErrorCollector error_collector; // NOTE(bill): Error recovery #define PARSER_MAX_FIX_COUNT 6 isize fix_count; TokenPos fix_prev_pos; }; // NOTE(bill): Just used to quickly check if there is double declaration in the same scope // No type checking actually happens // TODO(bill): Should this be completely handled in the semantic checker or is it better here? struct AstEntity { Token token; AstScope *parent; AstNode * declaration; }; struct AstScope { AstScope *parent; Map entities; // Key: Token.string }; struct Parser { gbArray(AstFile) files; gbArray(String) imports; isize import_index; }; enum AstNodeKind { AstNode_Invalid, AstNode_BasicLiteral, AstNode_Identifier, AstNode_ProcedureLiteral, AstNode_CompoundLiteral, AstNode__ExpressionBegin, AstNode_BadExpression, // NOTE(bill): Naughty expression AstNode_TagExpression, AstNode_UnaryExpression, AstNode_BinaryExpression, AstNode_ParenExpression, AstNode_CallExpression, AstNode_SelectorExpression, AstNode_IndexExpression, AstNode_SliceExpression, AstNode_CastExpression, AstNode_DereferenceExpression, AstNode__ExpressionEnd, AstNode__StatementBegin, AstNode_BadStatement, // NOTE(bill): Naughty statement AstNode_EmptyStatement, AstNode_TagStatement, AstNode_ExpressionStatement, AstNode_IncDecStatement, AstNode_AssignStatement, AstNode__ComplexStatementBegin, AstNode_BlockStatement, AstNode_IfStatement, AstNode_ReturnStatement, AstNode_ForStatement, AstNode_DeferStatement, AstNode_BranchStatement, AstNode__ComplexStatementEnd, AstNode__StatementEnd, AstNode__DeclarationBegin, AstNode_BadDeclaration, // NOTE(bill): Naughty declaration AstNode_VariableDeclaration, AstNode_ProcedureDeclaration, AstNode_TypeDeclaration, AstNode_AliasDeclaration, AstNode_ImportDeclaration, AstNode__DeclarationEnd, AstNode__TypeBegin, AstNode_Field, AstNode_ProcedureType, AstNode_PointerType, AstNode_ArrayType, AstNode_StructType, AstNode__TypeEnd, AstNode_Count, }; enum DeclarationKind { Declaration_Invalid, Declaration_Mutable, Declaration_Immutable, Declaration_Count, }; struct AstNode { AstNodeKind kind; AstNode *prev, *next; // NOTE(bill): allow for Linked list Type *type; union { // NOTE(bill): open/close for debugging/errors Token basic_literal; struct { Token token; AstEntity *entity; } identifier; struct { AstNode *type; // AstNode_ProcedureType AstNode *body; // AstNode_BlockStatement } procedure_literal; struct { AstNode *type_expression; AstNode *element_list; isize element_count; Token open, close; } compound_literal; struct { Token token; Token name; AstNode *expression; } tag_expression; struct { Token begin, end; } bad_expression; struct { Token op; AstNode *operand; } unary_expression; struct { Token op; AstNode *left, *right; } binary_expression; struct { AstNode *expression; Token open, close; } paren_expression; struct { Token token; AstNode *operand, *selector; } selector_expression; struct { AstNode *expression, *value; Token open, close; } index_expression; struct { Token token; AstNode *type_expression, *operand; } cast_expression; struct { AstNode *proc, *arg_list; isize arg_list_count; Token open, close; } call_expression; struct { Token op; AstNode *operand; } dereference_expression; struct { AstNode *expression; Token open, close; AstNode *low, *high, *max; b32 triple_indexed; // [(1st):2nd:3rd] } slice_expression; struct { Token begin, end; } bad_statement; struct { Token token; } empty_statement; struct { AstNode *expression; } expression_statement; struct { Token op; AstNode *expression; } inc_dec_statement; struct { Token token; Token name; AstNode *statement; } tag_statement; struct { Token op; AstNode *lhs_list, *rhs_list; isize lhs_count, rhs_count; } assign_statement; struct { AstNode *list; isize list_count; Token open, close; } block_statement; struct { Token token; AstNode *init; AstNode *cond; AstNode *body; AstNode *else_statement; } if_statement; struct { Token token; AstNode *results; // NOTE(bill): Return values isize result_count; } return_statement; struct { Token token; AstNode *init, *cond, *end; AstNode *body; } for_statement; struct { Token token; AstNode *statement; } defer_statement; struct { Token token; } branch_statement; struct { Token begin, end; } bad_declaration; struct { DeclarationKind kind; AstNode *name_list; AstNode *type_expression; AstNode *value_list; isize name_count, value_count; } variable_declaration; struct { AstNode *name_list; isize name_count; AstNode *type_expression; } field; // TODO(bill): Unify Procedure Declarations and Literals struct { DeclarationKind kind; AstNode *name; // AstNode_Identifier AstNode *type; // AstNode_ProcedureType AstNode *body; // AstNode_BlockStatement AstNode *tag_list; // AstNode_TagExpression isize tag_count; } procedure_declaration; struct { Token token; AstNode *name; // AstNode_Identifier AstNode *type_expression; } type_declaration; struct { Token token; AstNode *name; // AstNode_Identifier AstNode *type_expression; } alias_declaration; struct { Token token; Token filepath; } import_declaration; struct { Token token; AstNode *type_expression; } pointer_type; struct { Token token; AstNode *count; // NOTE(bill): Zero/NULL is probably a slice AstNode *element; } array_type; struct { Token token; AstNode *field_list; // AstNode_Field isize field_count; } struct_type; struct { Token token; AstNode *param_list; // AstNode_Field list isize param_count; AstNode *result_list; // type expression list isize result_count; } procedure_type; }; }; gb_inline AstScope *make_ast_scope(AstFile *f, AstScope *parent) { AstScope *scope = gb_alloc_item(gb_arena_allocator(&f->arena), AstScope); map_init(&scope->entities, gb_heap_allocator()); scope->parent = parent; return scope; } gb_inline b32 is_ast_node_expression(AstNode *node) { return gb_is_between(node->kind, AstNode__ExpressionBegin+1, AstNode__ExpressionEnd-1); } gb_inline b32 is_ast_node_statement(AstNode *node) { return gb_is_between(node->kind, AstNode__StatementBegin+1, AstNode__StatementEnd-1); } gb_inline b32 is_ast_node_complex_statement(AstNode *node) { return gb_is_between(node->kind, AstNode__ComplexStatementBegin+1, AstNode__ComplexStatementEnd-1); } gb_inline b32 is_ast_node_declaration(AstNode *node) { return gb_is_between(node->kind, AstNode__DeclarationBegin+1, AstNode__DeclarationEnd-1); } gb_inline b32 is_ast_node_type(AstNode *node) { return gb_is_between(node->kind, AstNode__TypeBegin+1, AstNode__TypeEnd-1); } Token ast_node_token(AstNode *node) { switch (node->kind) { case AstNode_BasicLiteral: return node->basic_literal; case AstNode_Identifier: return node->identifier.token; case AstNode_ProcedureLiteral: return ast_node_token(node->procedure_literal.type); case AstNode_CompoundLiteral: return ast_node_token(node->compound_literal.type_expression); case AstNode_TagExpression: return node->tag_expression.token; case AstNode_BadExpression: return node->bad_expression.begin; case AstNode_UnaryExpression: return node->unary_expression.op; case AstNode_BinaryExpression: return ast_node_token(node->binary_expression.left); case AstNode_ParenExpression: return node->paren_expression.open; case AstNode_CallExpression: return ast_node_token(node->call_expression.proc); case AstNode_SelectorExpression: return ast_node_token(node->selector_expression.selector); case AstNode_IndexExpression: return node->index_expression.open; case AstNode_SliceExpression: return node->slice_expression.open; case AstNode_CastExpression: return node->cast_expression.token; case AstNode_DereferenceExpression: return node->dereference_expression.op; case AstNode_BadStatement: return node->bad_statement.begin; case AstNode_EmptyStatement: return node->empty_statement.token; case AstNode_ExpressionStatement: return ast_node_token(node->expression_statement.expression); case AstNode_TagStatement: return node->tag_statement.token; case AstNode_IncDecStatement: return node->inc_dec_statement.op; case AstNode_AssignStatement: return node->assign_statement.op; case AstNode_BlockStatement: return node->block_statement.open; case AstNode_IfStatement: return node->if_statement.token; case AstNode_ReturnStatement: return node->return_statement.token; case AstNode_ForStatement: return node->for_statement.token; case AstNode_DeferStatement: return node->defer_statement.token; case AstNode_BranchStatement: return node->branch_statement.token; case AstNode_BadDeclaration: return node->bad_declaration.begin; case AstNode_VariableDeclaration: return ast_node_token(node->variable_declaration.name_list); case AstNode_ProcedureDeclaration: return node->procedure_declaration.name->identifier.token; case AstNode_TypeDeclaration: return node->type_declaration.token; case AstNode_AliasDeclaration: return node->alias_declaration.token; case AstNode_ImportDeclaration: return node->import_declaration.token; case AstNode_Field: { if (node->field.name_list) return ast_node_token(node->field.name_list); else return ast_node_token(node->field.type_expression); } case AstNode_ProcedureType: return node->procedure_type.token; case AstNode_PointerType: return node->pointer_type.token; case AstNode_ArrayType: return node->array_type.token; case AstNode_StructType: return node->struct_type.token; } return empty_token; ;} gb_inline void destroy_ast_scope(AstScope *scope) { // NOTE(bill): No need to free the actual pointer to the AstScope // as there should be enough room in the arena map_destroy(&scope->entities); } gb_inline AstScope *open_ast_scope(AstFile *f) { AstScope *scope = make_ast_scope(f, f->curr_scope); f->curr_scope = scope; f->scope_level++; return f->curr_scope; } gb_inline void close_ast_scope(AstFile *f) { GB_ASSERT_NOT_NULL(f->curr_scope); GB_ASSERT(f->scope_level > 0); { AstScope *parent = f->curr_scope->parent; if (f->curr_scope) { destroy_ast_scope(f->curr_scope); } f->curr_scope = parent; f->scope_level--; } } AstEntity *make_ast_entity(AstFile *f, Token token, AstNode *declaration, AstScope *parent) { AstEntity *entity = gb_alloc_item(gb_arena_allocator(&f->arena), AstEntity); entity->token = token; entity->declaration = declaration; entity->parent = parent; return entity; } u64 hash_token(Token t) { return hash_string(t.string); } AstEntity *ast_scope_lookup(AstScope *scope, Token token) { return map_get(&scope->entities, hash_token(token)); } AstEntity *ast_scope_insert(AstScope *scope, AstEntity entity) { AstEntity *prev = ast_scope_lookup(scope, entity.token); if (prev == NULL) { map_set(&scope->entities, hash_token(entity.token), entity); } return prev; } #define ast_file_err(f, token, fmt, ...) ast_file_err_(f, __FUNCTION__, token, fmt, ##__VA_ARGS__) void ast_file_err_(AstFile *file, char *function, Token token, char *fmt, ...) { // NOTE(bill): Duplicate error, skip it if (!token_pos_are_equal(file->error_collector.prev, token.pos)) { va_list va; file->error_collector.prev = token.pos; #if 0 gb_printf_err("%s()\n", function); #endif va_start(va, fmt); gb_printf_err("%.*s(%td:%td) Syntax error: %s\n", LIT(token.pos.file), token.pos.line, token.pos.column, gb_bprintf_va(fmt, va)); va_end(va); } file->error_collector.count++; } // NOTE(bill): And this below is why is I/we need a new language! Discriminated unions are a pain in C/C++ gb_inline AstNode *make_node(AstFile *f, AstNodeKind kind) { gbArena *arena = &f->arena; if (gb_arena_size_remaining(arena, GB_DEFAULT_MEMORY_ALIGNMENT) < gb_size_of(AstNode)) { // NOTE(bill): If a syntax error is so bad, just quit! gb_exit(1); } AstNode *node = gb_alloc_item(gb_arena_allocator(arena), AstNode); node->kind = kind; return node; } gb_inline AstNode *make_bad_expression(AstFile *f, Token begin, Token end) { AstNode *result = make_node(f, AstNode_BadExpression); result->bad_expression.begin = begin; result->bad_expression.end = end; return result; } gb_inline AstNode *make_tag_expression(AstFile *f, Token token, Token name, AstNode *expression) { AstNode *result = make_node(f, AstNode_TagExpression); result->tag_expression.token = token; result->tag_expression.name = name; result->tag_expression.expression = expression; return result; } gb_inline AstNode *make_tag_statement(AstFile *f, Token token, Token name, AstNode *statement) { AstNode *result = make_node(f, AstNode_TagStatement); result->tag_statement.token = token; result->tag_statement.name = name; result->tag_statement.statement = statement; return result; } gb_inline AstNode *make_unary_expression(AstFile *f, Token op, AstNode *operand) { AstNode *result = make_node(f, AstNode_UnaryExpression); result->unary_expression.op = op; result->unary_expression.operand = operand; return result; } gb_inline AstNode *make_binary_expression(AstFile *f, Token op, AstNode *left, AstNode *right) { AstNode *result = make_node(f, AstNode_BinaryExpression); if (left == NULL) { ast_file_err(f, op, "No lhs expression for binary expression `%.*s`", LIT(op.string)); left = make_bad_expression(f, op, op); } if (right == NULL) { ast_file_err(f, op, "No rhs expression for binary expression `%.*s`", LIT(op.string)); right = make_bad_expression(f, op, op); } result->binary_expression.op = op; result->binary_expression.left = left; result->binary_expression.right = right; return result; } gb_inline AstNode *make_paren_expression(AstFile *f, AstNode *expression, Token open, Token close) { AstNode *result = make_node(f, AstNode_ParenExpression); result->paren_expression.expression = expression; result->paren_expression.open = open; result->paren_expression.close = close; return result; } gb_inline AstNode *make_call_expression(AstFile *f, AstNode *proc, AstNode *arg_list, isize arg_list_count, Token open, Token close) { AstNode *result = make_node(f, AstNode_CallExpression); result->call_expression.proc = proc; result->call_expression.arg_list = arg_list; result->call_expression.arg_list_count = arg_list_count; result->call_expression.open = open; result->call_expression.close = close; return result; } gb_inline AstNode *make_selector_expression(AstFile *f, Token token, AstNode *operand, AstNode *selector) { AstNode *result = make_node(f, AstNode_SelectorExpression); result->selector_expression.operand = operand; result->selector_expression.selector = selector; return result; } gb_inline AstNode *make_index_expression(AstFile *f, AstNode *expression, AstNode *value, Token open, Token close) { AstNode *result = make_node(f, AstNode_IndexExpression); result->index_expression.expression = expression; result->index_expression.value = value; result->index_expression.open = open; result->index_expression.close = close; return result; } gb_inline AstNode *make_slice_expression(AstFile *f, AstNode *expression, Token open, Token close, AstNode *low, AstNode *high, AstNode *max, b32 triple_indexed) { AstNode *result = make_node(f, AstNode_SliceExpression); result->slice_expression.expression = expression; result->slice_expression.open = open; result->slice_expression.close = close; result->slice_expression.low = low; result->slice_expression.high = high; result->slice_expression.max = max; result->slice_expression.triple_indexed = triple_indexed; return result; } gb_inline AstNode *make_cast_expression(AstFile *f, Token token, AstNode *type_expression, AstNode *operand) { AstNode *result = make_node(f, AstNode_CastExpression); result->cast_expression.token = token; result->cast_expression.type_expression = type_expression; result->cast_expression.operand = operand; return result; } gb_inline AstNode *make_dereference_expression(AstFile *f, AstNode *operand, Token op) { AstNode *result = make_node(f, AstNode_DereferenceExpression); result->dereference_expression.operand = operand; result->dereference_expression.op = op; return result; } gb_inline AstNode *make_basic_literal(AstFile *f, Token basic_literal) { AstNode *result = make_node(f, AstNode_BasicLiteral); result->basic_literal = basic_literal; return result; } gb_inline AstNode *make_identifier(AstFile *f, Token token, AstEntity *entity = NULL) { AstNode *result = make_node(f, AstNode_Identifier); result->identifier.token = token; result->identifier.entity = entity; return result; } gb_inline AstNode *make_procedure_literal(AstFile *f, AstNode *type, AstNode *body) { AstNode *result = make_node(f, AstNode_ProcedureLiteral); result->procedure_literal.type = type; result->procedure_literal.body = body; return result; } gb_inline AstNode *make_compound_literal(AstFile *f, AstNode *type_expression, AstNode *element_list, isize element_count, Token open, Token close) { AstNode *result = make_node(f, AstNode_CompoundLiteral); result->compound_literal.type_expression = type_expression; result->compound_literal.element_list = element_list; result->compound_literal.element_count = element_count; result->compound_literal.open = open; result->compound_literal.close = close; return result; } gb_inline AstNode *make_bad_statement(AstFile *f, Token begin, Token end) { AstNode *result = make_node(f, AstNode_BadStatement); result->bad_statement.begin = begin; result->bad_statement.end = end; return result; } gb_inline AstNode *make_empty_statement(AstFile *f, Token token) { AstNode *result = make_node(f, AstNode_EmptyStatement); result->empty_statement.token = token; return result; } gb_inline AstNode *make_expression_statement(AstFile *f, AstNode *expression) { AstNode *result = make_node(f, AstNode_ExpressionStatement); result->expression_statement.expression = expression; return result; } gb_inline AstNode *make_inc_dec_statement(AstFile *f, Token op, AstNode *expression) { AstNode *result = make_node(f, AstNode_IncDecStatement); result->inc_dec_statement.op = op; result->inc_dec_statement.expression = expression; return result; } gb_inline AstNode *make_assign_statement(AstFile *f, Token op, AstNode *lhs_list, isize lhs_count, AstNode *rhs_list, isize rhs_count) { AstNode *result = make_node(f, AstNode_AssignStatement); result->assign_statement.op = op; result->assign_statement.lhs_list = lhs_list; result->assign_statement.lhs_count = lhs_count; result->assign_statement.rhs_list = rhs_list; result->assign_statement.rhs_count = rhs_count; return result; } gb_inline AstNode *make_block_statement(AstFile *f, AstNode *list, isize list_count, Token open, Token close) { AstNode *result = make_node(f, AstNode_BlockStatement); result->block_statement.list = list; result->block_statement.list_count = list_count; result->block_statement.open = open; result->block_statement.close = close; return result; } gb_inline AstNode *make_if_statement(AstFile *f, Token token, AstNode *init, AstNode *cond, AstNode *body, AstNode *else_statement) { AstNode *result = make_node(f, AstNode_IfStatement); result->if_statement.token = token; result->if_statement.init = init; result->if_statement.cond = cond; result->if_statement.body = body; result->if_statement.else_statement = else_statement; return result; } gb_inline AstNode *make_return_statement(AstFile *f, Token token, AstNode *results, isize result_count) { AstNode *result = make_node(f, AstNode_ReturnStatement); result->return_statement.token = token; result->return_statement.results = results; result->return_statement.result_count = result_count; return result; } gb_inline AstNode *make_for_statement(AstFile *f, Token token, AstNode *init, AstNode *cond, AstNode *end, AstNode *body) { AstNode *result = make_node(f, AstNode_ForStatement); result->for_statement.token = token; result->for_statement.init = init; result->for_statement.cond = cond; result->for_statement.end = end; result->for_statement.body = body; return result; } gb_inline AstNode *make_defer_statement(AstFile *f, Token token, AstNode *statement) { AstNode *result = make_node(f, AstNode_DeferStatement); result->defer_statement.token = token; result->defer_statement.statement = statement; return result; } gb_inline AstNode *make_branch_statement(AstFile *f, Token token) { AstNode *result = make_node(f, AstNode_BranchStatement); result->branch_statement.token = token; return result; } gb_inline AstNode *make_bad_declaration(AstFile *f, Token begin, Token end) { AstNode *result = make_node(f, AstNode_BadDeclaration); result->bad_declaration.begin = begin; result->bad_declaration.end = end; return result; } gb_inline AstNode *make_variable_declaration(AstFile *f, DeclarationKind kind, AstNode *name_list, isize name_count, AstNode *type_expression, AstNode *value_list, isize value_count) { AstNode *result = make_node(f, AstNode_VariableDeclaration); result->variable_declaration.kind = kind; result->variable_declaration.name_list = name_list; result->variable_declaration.name_count = name_count; result->variable_declaration.type_expression = type_expression; result->variable_declaration.value_list = value_list; result->variable_declaration.value_count = value_count; return result; } gb_inline AstNode *make_field(AstFile *f, AstNode *name_list, isize name_count, AstNode *type_expression) { AstNode *result = make_node(f, AstNode_Field); result->field.name_list = name_list; result->field.name_count = name_count; result->field.type_expression = type_expression; return result; } gb_inline AstNode *make_procedure_type(AstFile *f, Token token, AstNode *param_list, isize param_count, AstNode *result_list, isize result_count) { AstNode *result = make_node(f, AstNode_ProcedureType); result->procedure_type.token = token; result->procedure_type.param_list = param_list; result->procedure_type.param_count = param_count; result->procedure_type.result_list = result_list; result->procedure_type.result_count = result_count; return result; } gb_inline AstNode *make_procedure_declaration(AstFile *f, DeclarationKind kind, AstNode *name, AstNode *procedure_type, AstNode *body, AstNode *tag_list, isize tag_count) { AstNode *result = make_node(f, AstNode_ProcedureDeclaration); result->procedure_declaration.kind = kind; result->procedure_declaration.name = name; result->procedure_declaration.type = procedure_type; result->procedure_declaration.body = body; result->procedure_declaration.tag_list = tag_list; result->procedure_declaration.tag_count = tag_count; return result; } gb_inline AstNode *make_pointer_type(AstFile *f, Token token, AstNode *type_expression) { AstNode *result = make_node(f, AstNode_PointerType); result->pointer_type.token = token; result->pointer_type.type_expression = type_expression; return result; } gb_inline AstNode *make_array_type(AstFile *f, Token token, AstNode *count, AstNode *element) { AstNode *result = make_node(f, AstNode_ArrayType); result->array_type.token = token; result->array_type.count = count; result->array_type.element = element; return result; } gb_inline AstNode *make_struct_type(AstFile *f, Token token, AstNode *field_list, isize field_count) { AstNode *result = make_node(f, AstNode_StructType); result->struct_type.token = token; result->struct_type.field_list = field_list; result->struct_type.field_count = field_count; return result; } gb_inline AstNode *make_type_declaration(AstFile *f, Token token, AstNode *name, AstNode *type_expression) { AstNode *result = make_node(f, AstNode_TypeDeclaration); result->type_declaration.token = token; result->type_declaration.name = name; result->type_declaration.type_expression = type_expression; return result; } gb_inline AstNode *make_alias_declaration(AstFile *f, Token token, AstNode *name, AstNode *type_expression) { AstNode *result = make_node(f, AstNode_AliasDeclaration); result->alias_declaration.token = token; result->alias_declaration.name = name; result->alias_declaration.type_expression = type_expression; return result; } gb_inline AstNode *make_import_declaration(AstFile *f, Token token, Token filepath) { AstNode *result = make_node(f, AstNode_ImportDeclaration); result->import_declaration.token = token; result->import_declaration.filepath = filepath; return result; } gb_inline b32 next_token(AstFile *f) { if (f->cursor+1 < f->tokens + gb_array_count(f->tokens)) { f->cursor++; return true; } else { ast_file_err(f, f->cursor[0], "Token is EOF"); return false; } } gb_inline Token expect_token(AstFile *f, TokenKind kind) { Token prev = f->cursor[0]; if (prev.kind != kind) { ast_file_err(f, f->cursor[0], "Expected `%.*s`, got `%.*s`", LIT(token_strings[kind]), LIT(token_strings[prev.kind])); } next_token(f); return prev; } gb_inline Token expect_operator(AstFile *f) { Token prev = f->cursor[0]; if (!gb_is_between(prev.kind, Token__OperatorBegin+1, Token__OperatorEnd-1)) { ast_file_err(f, f->cursor[0], "Expected an operator, got `%.*s`", LIT(token_strings[prev.kind])); } next_token(f); return prev; } gb_inline Token expect_keyword(AstFile *f) { Token prev = f->cursor[0]; if (!gb_is_between(prev.kind, Token__KeywordBegin+1, Token__KeywordEnd-1)) { ast_file_err(f, f->cursor[0], "Expected a keyword, got `%.*s`", LIT(token_strings[prev.kind])); } next_token(f); return prev; } gb_inline b32 allow_token(AstFile *f, TokenKind kind) { Token prev = f->cursor[0]; if (prev.kind == kind) { next_token(f); return true; } return false; } gb_internal void add_ast_entity(AstFile *f, AstScope *scope, AstNode *declaration, AstNode *name_list) { for (AstNode *n = name_list; n != NULL; n = n->next) { if (n->kind != AstNode_Identifier) { ast_file_err(f, ast_node_token(declaration), "Identifier is already declared or resolved"); continue; } AstEntity *entity = make_ast_entity(f, n->identifier.token, declaration, scope); n->identifier.entity = entity; AstEntity *insert_entity = ast_scope_insert(scope, *entity); if (insert_entity != NULL && !are_strings_equal(insert_entity->token.string, make_string("_"))) { ast_file_err(f, entity->token, "There is already a previous declaration of `%.*s` in the current scope at\n" "\t%.*s(%td:%td)", LIT(insert_entity->token.string), LIT(insert_entity->token.pos.file), insert_entity->token.pos.line, insert_entity->token.pos.column); } } } void fix_advance_to_next_statement(AstFile *f) { #if 0 for (;;) { Token t = f->cursor[0]; switch (t.kind) { case Token_EOF: return; case Token_type: case Token_break: case Token_continue: case Token_fallthrough: case Token_if: case Token_for: case Token_defer: case Token_return: if (token_pos_are_equal(t.pos, f->fix_prev_pos) && f->fix_count < PARSER_MAX_FIX_COUNT) { f->fix_count++; return; } if (token_pos_cmp(f->fix_prev_pos, t.pos) < 0) { f->fix_prev_pos = t.pos; f->fix_count = 0; // NOTE(bill): Reset return; } } next_token(f); } #endif } AstNode *parse_expression(AstFile *f, b32 lhs); AstNode *parse_procedure_type(AstFile *f, AstScope **scope_); AstNode *parse_statement_list(AstFile *f, isize *list_count_); AstNode *parse_statement(AstFile *f); AstNode *parse_body(AstFile *f, AstScope *scope); AstNode *parse_identifier(AstFile *f) { Token token = f->cursor[0]; if (token.kind == Token_Identifier) { next_token(f); } else { token.string = make_string("_"); expect_token(f, Token_Identifier); } return make_identifier(f, token); } AstNode *parse_tag_expression(AstFile *f, AstNode *expression) { Token token = expect_token(f, Token_Hash); Token name = expect_token(f, Token_Identifier); return make_tag_expression(f, token, name, expression); } AstNode *parse_tag_statement(AstFile *f, AstNode *statement) { Token token = expect_token(f, Token_Hash); Token name = expect_token(f, Token_Identifier); return make_tag_statement(f, token, name, statement); } AstNode *unparen_expression(AstNode *node) { for (;;) { if (node->kind != AstNode_ParenExpression) return node; node = node->paren_expression.expression; } } AstNode *parse_value(AstFile *f); AstNode *parse_element_list(AstFile *f, isize *element_count_) { AstNode *root = NULL; AstNode *curr = NULL; isize element_count = 0; while (f->cursor[0].kind != Token_CloseBrace && f->cursor[0].kind != Token_EOF) { AstNode *elem = parse_value(f); #if 0 // TODO(bill): Designated Initializers if (f->cursor[0].kind == Token_Eq) { Token eq = expect_token(f, Token_Eq); } #endif DLIST_APPEND(root, curr, elem); element_count++; if (f->cursor[0].kind != Token_Comma) break; next_token(f); } if (element_count_) *element_count_ = element_count; return root; } AstNode *parse_literal_value(AstFile *f, AstNode *type_expression) { AstNode *element_list = NULL; isize element_count = 0; Token open = expect_token(f, Token_OpenBrace); f->expression_level++; if (f->cursor[0].kind != Token_CloseBrace) element_list = parse_element_list(f, &element_count); f->expression_level--; Token close = expect_token(f, Token_CloseBrace); return make_compound_literal(f, type_expression, element_list, element_count, open, close); } AstNode *parse_value(AstFile *f) { if (f->cursor[0].kind == Token_OpenBrace) return parse_literal_value(f, NULL); AstNode *value = parse_expression(f, false); return value; } AstNode *parse_identifier_or_type(AstFile *f); AstNode *parse_operand(AstFile *f, b32 lhs) { AstNode *operand = NULL; // Operand switch (f->cursor[0].kind) { case Token_Identifier: operand = parse_identifier(f); if (!lhs) { // TODO(bill): Handle? } return operand; case Token_Integer: case Token_Float: case Token_String: case Token_Rune: operand = make_basic_literal(f, f->cursor[0]); next_token(f); return operand; case Token_OpenParen: { Token open, close; // NOTE(bill): Skip the Paren Expression open = expect_token(f, Token_OpenParen); f->expression_level++; operand = parse_expression(f, false); f->expression_level--; close = expect_token(f, Token_CloseParen); return make_paren_expression(f, operand, open, close); } case Token_Hash: { operand = parse_tag_expression(f, NULL); operand->tag_expression.expression = parse_expression(f, false); return operand; } // Parse Procedure Type or Literal case Token_proc: { AstScope *scope = NULL; AstNode *type = parse_procedure_type(f, &scope); if (f->cursor[0].kind != Token_OpenBrace) { return type; } else { AstNode *body; f->expression_level++; body = parse_body(f, scope); f->expression_level--; return make_procedure_literal(f, type, body); } } default: { AstNode *type = parse_identifier_or_type(f); if (type != NULL) { // NOTE(bill): Sanity check as identifiers should be handled already GB_ASSERT_MSG(type->kind != AstNode_Identifier, "Type Cannot be identifier"); return type; } } } Token begin = f->cursor[0]; ast_file_err(f, begin, "Expected an operand"); fix_advance_to_next_statement(f); return make_bad_expression(f, begin, f->cursor[0]); } b32 is_literal_type(AstNode *node) { switch (node->kind) { case AstNode_BadExpression: case AstNode_Identifier: case AstNode_ArrayType: case AstNode_StructType: return true; } return false; } AstNode *parse_atom_expression(AstFile *f, b32 lhs) { AstNode *operand = parse_operand(f, lhs); b32 loop = true; while (loop) { switch (f->cursor[0].kind) { case Token_OpenParen: { if (lhs) { // TODO(bill): Handle this shit! Is this even allowed in this language?! } AstNode *arg_list = NULL; AstNode *arg_list_curr = NULL; isize arg_list_count = 0; Token open_paren, close_paren; f->expression_level++; open_paren = expect_token(f, Token_OpenParen); while (f->cursor[0].kind != Token_CloseParen && f->cursor[0].kind != Token_EOF) { if (f->cursor[0].kind == Token_Comma) ast_file_err(f, f->cursor[0], "Expected an expression not a ,"); DLIST_APPEND(arg_list, arg_list_curr, parse_expression(f, false)); arg_list_count++; if (f->cursor[0].kind != Token_Comma) { if (f->cursor[0].kind == Token_CloseParen) break; } next_token(f); } f->expression_level--; close_paren = expect_token(f, Token_CloseParen); operand = make_call_expression(f, operand, arg_list, arg_list_count, open_paren, close_paren); } break; case Token_Period: { Token token = f->cursor[0]; next_token(f); if (lhs) { // TODO(bill): handle this } switch (f->cursor[0].kind) { case Token_Identifier: operand = make_selector_expression(f, token, operand, parse_identifier(f)); break; default: { ast_file_err(f, f->cursor[0], "Expected a selector"); next_token(f); operand = make_selector_expression(f, f->cursor[0], operand, NULL); } break; } } break; case Token_OpenBracket: { if (lhs) { // TODO(bill): Handle this } Token open, close; AstNode *indices[3] = {}; f->expression_level++; open = expect_token(f, Token_OpenBracket); if (f->cursor[0].kind != Token_Colon) indices[0] = parse_expression(f, false); isize colon_count = 0; Token colons[2] = {}; while (f->cursor[0].kind == Token_Colon && colon_count < 2) { colons[colon_count++] = f->cursor[0]; next_token(f); if (f->cursor[0].kind != Token_Colon && f->cursor[0].kind != Token_CloseBracket && f->cursor[0].kind != Token_EOF) { indices[colon_count] = parse_expression(f, false); } } f->expression_level--; close = expect_token(f, Token_CloseBracket); if (colon_count == 0) { operand = make_index_expression(f, operand, indices[0], open, close); } else { b32 triple_indexed = false; if (colon_count == 2) { triple_indexed = true; if (indices[1] == NULL) { ast_file_err(f, colons[0], "Second index is required in a triple indexed slice"); indices[1] = make_bad_expression(f, colons[0], colons[1]); } if (indices[2] == NULL) { ast_file_err(f, colons[1], "Third index is required in a triple indexed slice"); indices[2] = make_bad_expression(f, colons[1], close); } } operand = make_slice_expression(f, operand, open, close, indices[0], indices[1], indices[2], triple_indexed); } } break; case Token_Pointer: // Deference operand = make_dereference_expression(f, operand, expect_token(f, Token_Pointer)); break; case Token_OpenBrace: { if (is_literal_type(operand) && f->expression_level >= 0) { gb_printf_err("here\n"); if (lhs) { // TODO(bill): Handle this } operand = parse_literal_value(f, operand); } else { loop = false; } } break; default: loop = false; break; } lhs = false; // NOTE(bill): 'tis not lhs anymore } return operand; } AstNode *parse_type(AstFile *f); AstNode *parse_unary_expression(AstFile *f, b32 lhs) { switch (f->cursor[0].kind) { case Token_Pointer: case Token_Add: case Token_Sub: case Token_Not: case Token_Xor: { AstNode *operand; Token op = f->cursor[0]; next_token(f); operand = parse_unary_expression(f, false); return make_unary_expression(f, op, operand); } break; case Token_cast: { AstNode *type_expression, *operand; Token token = f->cursor[0]; next_token(f); expect_token(f, Token_OpenParen); type_expression = parse_type(f); expect_token(f, Token_CloseParen); operand = parse_unary_expression(f, false); return make_cast_expression(f, token, type_expression, operand); } break; } return parse_atom_expression(f, lhs); } AstNode *parse_binary_expression(AstFile *f, b32 lhs, i32 prec_in) { AstNode *expression = parse_unary_expression(f, lhs); for (i32 prec = token_precedence(f->cursor[0]); prec >= prec_in; prec--) { for (;;) { AstNode *right; Token op = f->cursor[0]; i32 op_prec = token_precedence(op); if (op_prec != prec) break; expect_operator(f); // NOTE(bill): error checks too if (lhs) { // TODO(bill): error checking lhs = false; } right = parse_binary_expression(f, false, prec+1); if (!right) ast_file_err(f, op, "Expected expression on the right hand side of the binary operator"); expression = make_binary_expression(f, op, expression, right); } } return expression; } AstNode *parse_expression(AstFile *f, b32 lhs) { return parse_binary_expression(f, lhs, 0+1); } AstNode *parse_expression_list(AstFile *f, b32 lhs, isize *list_count_) { AstNode *list_root = NULL; AstNode *list_curr = NULL; isize list_count = 0; do { DLIST_APPEND(list_root, list_curr, parse_expression(f, lhs)); list_count++; if (f->cursor[0].kind != Token_Comma || f->cursor[0].kind == Token_EOF) break; next_token(f); } while (true); if (list_count_) *list_count_ = list_count; return list_root; } AstNode *parse_lhs_expression_list(AstFile *f, isize *list_count) { return parse_expression_list(f, true, list_count); } AstNode *parse_rhs_expression_list(AstFile *f, isize *list_count) { return parse_expression_list(f, false, list_count); } AstNode *parse_declaration(AstFile *f, AstNode *name_list, isize name_count); AstNode *parse_simple_statement(AstFile *f) { isize lhs_count = 0, rhs_count = 0; AstNode *lhs_expression_list = parse_lhs_expression_list(f, &lhs_count); AstNode *statement = NULL; Token token = f->cursor[0]; switch (token.kind) { case Token_Eq: case Token_AddEq: case Token_SubEq: case Token_MulEq: case Token_QuoEq: case Token_ModEq: case Token_AndEq: case Token_OrEq: case Token_XorEq: case Token_AndNotEq: case Token_CmpAndEq: case Token_CmpOrEq: { if (f->curr_scope == f->file_scope) { ast_file_err(f, f->cursor[0], "You cannot use a simple statement in the file scope"); return make_bad_statement(f, f->cursor[0], f->cursor[0]); } next_token(f); AstNode *rhs_expression_list = parse_rhs_expression_list(f, &rhs_count); if (rhs_expression_list == NULL) { ast_file_err(f, token, "No right-hand side in assignment statement."); return make_bad_statement(f, token, f->cursor[0]); } return make_assign_statement(f, token, lhs_expression_list, lhs_count, rhs_expression_list, rhs_count); } break; case Token_Colon: // Declare return parse_declaration(f, lhs_expression_list, lhs_count); } if (lhs_count > 1) { ast_file_err(f, token, "Expected 1 expression"); return make_bad_statement(f, token, f->cursor[0]); } token = f->cursor[0]; switch (token.kind) { case Token_Increment: case Token_Decrement: if (f->curr_scope == f->file_scope) { ast_file_err(f, f->cursor[0], "You cannot use a simple statement in the file scope"); return make_bad_statement(f, f->cursor[0], f->cursor[0]); } statement = make_inc_dec_statement(f, token, lhs_expression_list); next_token(f); return statement; } return make_expression_statement(f, lhs_expression_list); } AstNode *parse_block_statement(AstFile *f) { if (f->curr_scope == f->file_scope) { ast_file_err(f, f->cursor[0], "You cannot use a block statement in the file scope"); return make_bad_statement(f, f->cursor[0], f->cursor[0]); } AstNode *block_statement; open_ast_scope(f); block_statement = parse_body(f, f->curr_scope); close_ast_scope(f); return block_statement; } AstNode *convert_statement_to_expression(AstFile *f, AstNode *statement, String kind) { if (statement == NULL) return NULL; if (statement->kind == AstNode_ExpressionStatement) return statement->expression_statement.expression; ast_file_err(f, f->cursor[0], "Expected `%.*s`, found a simple statement.", LIT(kind)); return make_bad_expression(f, f->cursor[0], f->cursor[1]); } AstNode *parse_identfier_list(AstFile *f, isize *list_count_) { AstNode *list_root = NULL; AstNode *list_curr = NULL; isize list_count = 0; do { DLIST_APPEND(list_root, list_curr, parse_identifier(f)); list_count++; if (f->cursor[0].kind != Token_Comma || f->cursor[0].kind == Token_EOF) break; next_token(f); } while (true); if (list_count_) *list_count_ = list_count; return list_root; } AstNode *parse_type_attempt(AstFile *f) { AstNode *type = parse_identifier_or_type(f); if (type != NULL) { // TODO(bill): Handle? } return type; } AstNode *parse_type(AstFile *f) { AstNode *type = parse_type_attempt(f); if (type == NULL) { Token token = f->cursor[0]; ast_file_err(f, token, "Expected a type"); next_token(f); return make_bad_expression(f, token, f->cursor[0]); } return type; } AstNode *parse_field_declaration(AstFile *f, AstScope *scope) { AstNode *name_list = NULL; isize name_count = 0; name_list = parse_lhs_expression_list(f, &name_count); if (name_count == 0) ast_file_err(f, f->cursor[0], "Empty field declaration"); expect_token(f, Token_Colon); AstNode *type_expression = parse_type_attempt(f); if (type_expression == NULL) ast_file_err(f, f->cursor[0], "Expected a type for this field declaration"); AstNode *field = make_field(f, name_list, name_count, type_expression); add_ast_entity(f, scope, field, name_list); return field; } Token parse_procedure_signature(AstFile *f, AstScope *scope, AstNode **param_list, isize *param_count, AstNode **result_list, isize *result_count); AstNode *parse_procedure_type(AstFile *f, AstScope **scope_) { AstScope *scope = make_ast_scope(f, f->file_scope); // Procedure's scope AstNode *params = NULL; AstNode *results = NULL; isize param_count = 0; isize result_count = 0; Token proc_token = parse_procedure_signature(f, scope, ¶ms, ¶m_count, &results, &result_count); if (scope_) *scope_ = scope; return make_procedure_type(f, proc_token, params, param_count, results, result_count); } AstNode *parse_parameter_list(AstFile *f, AstScope *scope, isize *param_count_) { AstNode *param_list = NULL; AstNode *param_list_curr = NULL; isize param_count = 0; while (f->cursor[0].kind == Token_Identifier) { AstNode *field = parse_field_declaration(f, scope); DLIST_APPEND(param_list, param_list_curr, field); param_count += field->field.name_count; if (f->cursor[0].kind != Token_Comma) break; next_token(f); } if (param_count_) *param_count_ = param_count; return param_list; } AstNode *parse_identifier_or_type(AstFile *f) { switch (f->cursor[0].kind) { case Token_Identifier: return parse_identifier(f); case Token_Pointer: return make_pointer_type(f, expect_token(f, Token_Pointer), parse_type(f)); case Token_OpenBracket: { f->expression_level++; Token token = expect_token(f, Token_OpenBracket); AstNode *count_expression = NULL; if (f->cursor[0].kind != Token_CloseBracket) count_expression = parse_expression(f, false); expect_token(f, Token_CloseBracket); f->expression_level--; return make_array_type(f, token, count_expression, parse_type(f)); } case Token_struct: { Token token = expect_token(f, Token_struct); Token open, close; AstNode *params = NULL; isize param_count = 0; AstScope *scope = make_ast_scope(f, NULL); // NOTE(bill): The struct needs its own scope with NO parent open = expect_token(f, Token_OpenBrace); params = parse_parameter_list(f, scope, ¶m_count); close = expect_token(f, Token_CloseBrace); return make_struct_type(f, token, params, param_count); } case Token_proc: return parse_procedure_type(f, NULL); case Token_OpenParen: { // NOTE(bill): Skip the paren expression AstNode *type_expression; Token open, close; open = expect_token(f, Token_OpenParen); type_expression = parse_type(f); close = expect_token(f, Token_CloseParen); return make_paren_expression(f, type_expression, open, close); } // TODO(bill): Why is this even allowed? Is this a parsing error? case Token_Colon: break; case Token_Eq: if (f->cursor[-1].kind == Token_Colon) break; // fallthrough default: ast_file_err(f, f->cursor[0], "Expected a type after `%.*s`, got `%.*s`", LIT(f->cursor[-1].string), LIT(f->cursor[0].string)); break; } return NULL; } AstNode *parse_results(AstFile *f, AstScope *scope, isize *result_count) { if (allow_token(f, Token_ArrowRight)) { if (f->cursor[0].kind == Token_OpenParen) { expect_token(f, Token_OpenParen); AstNode *list = NULL; AstNode *list_curr = NULL; isize count = 0; while (f->cursor[0].kind != Token_CloseParen && f->cursor[0].kind != Token_EOF) { DLIST_APPEND(list, list_curr, parse_type(f)); count++; if (f->cursor[0].kind != Token_Comma) break; next_token(f); } expect_token(f, Token_CloseParen); if (result_count) *result_count = count; return list; } AstNode *result = parse_type(f); if (result_count) *result_count = 1; return result; } if (result_count) *result_count = 0; return NULL; } Token parse_procedure_signature(AstFile *f, AstScope *scope, AstNode **param_list, isize *param_count, AstNode **result_list, isize *result_count) { Token proc_token = expect_token(f, Token_proc); expect_token(f, Token_OpenParen); *param_list = parse_parameter_list(f, scope, param_count); expect_token(f, Token_CloseParen); *result_list = parse_results(f, scope, result_count); return proc_token; } AstNode *parse_body(AstFile *f, AstScope *scope) { AstNode *statement_list = NULL; isize statement_list_count = 0; Token open, close; open = expect_token(f, Token_OpenBrace); statement_list = parse_statement_list(f, &statement_list_count); close = expect_token(f, Token_CloseBrace); return make_block_statement(f, statement_list, statement_list_count, open, close); } AstNode *parse_procedure_declaration(AstFile *f, Token proc_token, AstNode *name, DeclarationKind kind) { AstNode *param_list = NULL; AstNode *result_list = NULL; isize param_count = 0; isize result_count = 0; AstScope *scope = open_ast_scope(f); parse_procedure_signature(f, scope, ¶m_list, ¶m_count, &result_list, &result_count); AstNode *body = NULL; AstNode *tag_list = NULL; AstNode *tag_list_curr = NULL; isize tag_count = 0; while (f->cursor[0].kind == Token_Hash) { DLIST_APPEND(tag_list, tag_list_curr, parse_tag_expression(f, NULL)); tag_count++; } if (f->cursor[0].kind == Token_OpenBrace) { body = parse_body(f, scope); } close_ast_scope(f); AstNode *proc_type = make_procedure_type(f, proc_token, param_list, param_count, result_list, result_count); return make_procedure_declaration(f, kind, name, proc_type, body, tag_list, tag_count); } AstNode *parse_declaration(AstFile *f, AstNode *name_list, isize name_count) { AstNode *value_list = NULL; AstNode *type_expression = NULL; isize value_count = 0; if (allow_token(f, Token_Colon)) { type_expression = parse_identifier_or_type(f); } else if (f->cursor[0].kind != Token_Eq && f->cursor[0].kind != Token_Semicolon) { ast_file_err(f, f->cursor[0], "Expected type separator `:` or `=`"); } DeclarationKind declaration_kind = Declaration_Mutable; if (f->cursor[0].kind == Token_Eq || f->cursor[0].kind == Token_Colon) { if (f->cursor[0].kind == Token_Colon) declaration_kind = Declaration_Immutable; next_token(f); if (f->cursor[0].kind == Token_proc) { // NOTE(bill): Procedure declarations Token proc_token = f->cursor[0]; AstNode *name = name_list; if (name_count != 1) { ast_file_err(f, proc_token, "You can only declare one procedure at a time (at the moment)"); return make_bad_declaration(f, name->identifier.token, proc_token); } AstNode *procedure_declaration = parse_procedure_declaration(f, proc_token, name, declaration_kind); add_ast_entity(f, f->curr_scope, procedure_declaration, name_list); return procedure_declaration; } else { value_list = parse_rhs_expression_list(f, &value_count); if (value_count > name_count) { ast_file_err(f, f->cursor[0], "Too many values on the right hand side of the declaration"); } else if (value_count < name_count && declaration_kind == Declaration_Immutable) { ast_file_err(f, f->cursor[0], "All constant declarations must be defined"); } else if (value_list == NULL) { ast_file_err(f, f->cursor[0], "Expected an expression for this declaration"); } } } if (declaration_kind == Declaration_Mutable) { if (type_expression == NULL && value_list == NULL) { ast_file_err(f, f->cursor[0], "Missing variable type or initialization"); return make_bad_declaration(f, f->cursor[0], f->cursor[0]); } } else if (declaration_kind == Declaration_Immutable) { if (type_expression == NULL && value_list == NULL && name_count > 0) { ast_file_err(f, f->cursor[0], "Missing constant value"); return make_bad_declaration(f, f->cursor[0], f->cursor[0]); } } else { Token begin = f->cursor[0]; ast_file_err(f, begin, "Unknown type of variable declaration"); fix_advance_to_next_statement(f); return make_bad_declaration(f, begin, f->cursor[0]); } AstNode *variable_declaration = make_variable_declaration(f, declaration_kind, name_list, name_count, type_expression, value_list, value_count); add_ast_entity(f, f->curr_scope, variable_declaration, name_list); return variable_declaration; } AstNode *parse_if_statement(AstFile *f) { if (f->curr_scope == f->file_scope) { ast_file_err(f, f->cursor[0], "You cannot use an if statement in the file scope"); return make_bad_statement(f, f->cursor[0], f->cursor[0]); } Token token = expect_token(f, Token_if); AstNode *init = NULL; AstNode *cond = NULL; AstNode *body = NULL; AstNode *else_statement = NULL; open_ast_scope(f); defer (close_ast_scope(f)); isize prev_level = f->expression_level; f->expression_level = -1; if (allow_token(f, Token_Semicolon)) { cond = parse_expression(f, false); } else { init = parse_simple_statement(f); if (allow_token(f, Token_Semicolon)) { cond = parse_expression(f, false); } else { cond = convert_statement_to_expression(f, init, make_string("boolean expression")); init = NULL; } } f->expression_level = prev_level; if (cond == NULL) { ast_file_err(f, f->cursor[0], "Expected condition for if statement"); } body = parse_block_statement(f); if (allow_token(f, Token_else)) { switch (f->cursor[0].kind) { case Token_if: else_statement = parse_if_statement(f); break; case Token_OpenBrace: else_statement = parse_block_statement(f); break; default: ast_file_err(f, f->cursor[0], "Expected if statement block statement"); else_statement = make_bad_statement(f, f->cursor[0], f->cursor[1]); break; } } return make_if_statement(f, token, init, cond, body, else_statement); } AstNode *parse_return_statement(AstFile *f) { if (f->curr_scope == f->file_scope) { ast_file_err(f, f->cursor[0], "You cannot use a return statement in the file scope"); return make_bad_statement(f, f->cursor[0], f->cursor[0]); } Token token = expect_token(f, Token_return); AstNode *result = NULL; isize result_count = 0; if (f->cursor[0].kind != Token_Semicolon) result = parse_rhs_expression_list(f, &result_count); expect_token(f, Token_Semicolon); return make_return_statement(f, token, result, result_count); } AstNode *parse_for_statement(AstFile *f) { if (f->curr_scope == f->file_scope) { ast_file_err(f, f->cursor[0], "You cannot use a for statement in the file scope"); return make_bad_statement(f, f->cursor[0], f->cursor[0]); } Token token = expect_token(f, Token_for); open_ast_scope(f); defer (close_ast_scope(f)); AstNode *init = NULL; AstNode *cond = NULL; AstNode *end = NULL; AstNode *body = NULL; if (f->cursor[0].kind != Token_OpenBrace) { isize prev_level = f->expression_level; f->expression_level = -1; if (f->cursor[0].kind != Token_Semicolon) { cond = parse_simple_statement(f); if (is_ast_node_complex_statement(cond)) { ast_file_err(f, f->cursor[0], "You are not allowed that type of statement in a for statement, it is too complex!"); } } if (allow_token(f, Token_Semicolon)) { init = cond; cond = NULL; if (f->cursor[0].kind != Token_Semicolon) { cond = parse_simple_statement(f); } expect_token(f, Token_Semicolon); if (f->cursor[0].kind != Token_OpenBrace) { end = parse_simple_statement(f); } } f->expression_level = prev_level; } body = parse_block_statement(f); cond = convert_statement_to_expression(f, cond, make_string("boolean expression")); return make_for_statement(f, token, init, cond, end, body); } AstNode *parse_defer_statement(AstFile *f) { if (f->curr_scope == f->file_scope) { ast_file_err(f, f->cursor[0], "You cannot use a defer statement in the file scope"); return make_bad_statement(f, f->cursor[0], f->cursor[0]); } Token token = expect_token(f, Token_defer); AstNode *statement = parse_statement(f); switch (statement->kind) { case AstNode_EmptyStatement: ast_file_err(f, token, "Empty statement after defer (e.g. `;`)"); break; case AstNode_DeferStatement: ast_file_err(f, token, "You cannot defer a defer statement"); break; case AstNode_ReturnStatement: ast_file_err(f, token, "You cannot a return statement"); break; } return make_defer_statement(f, token, statement); } AstNode *parse_type_declaration(AstFile *f) { Token token = expect_token(f, Token_type); AstNode *name = parse_identifier(f); expect_token(f, Token_Colon); AstNode *type_expression = parse_type(f); AstNode *type_declaration = make_type_declaration(f, token, name, type_expression); if (type_expression->kind != AstNode_StructType && type_expression->kind != AstNode_ProcedureType) expect_token(f, Token_Semicolon); return type_declaration; } AstNode *parse_alias_declaration(AstFile *f) { Token token = expect_token(f, Token_alias); AstNode *name = parse_identifier(f); expect_token(f, Token_Colon); AstNode *type_expression = parse_type(f); AstNode *alias_declaration = make_alias_declaration(f, token, name, type_expression); if (type_expression->kind != AstNode_StructType && type_expression->kind != AstNode_ProcedureType) expect_token(f, Token_Semicolon); return alias_declaration; } AstNode *parse_import_declaration(AstFile *f) { Token token = expect_token(f, Token_import); Token filepath = expect_token(f, Token_String); if (f->curr_scope == f->file_scope) { return make_import_declaration(f, token, filepath); } ast_file_err(f, token, "You cannot `import` within a procedure. This must be done at the file scope."); return make_bad_declaration(f, token, filepath); } AstNode *parse_statement(AstFile *f) { AstNode *s = NULL; Token token = f->cursor[0]; switch (token.kind) { case Token_type: return parse_type_declaration(f); case Token_alias: return parse_alias_declaration(f); case Token_import: return parse_import_declaration(f); // Operands case Token_Identifier: case Token_Integer: case Token_Float: case Token_Rune: case Token_String: case Token_OpenParen: // Unary Operators case Token_Add: case Token_Sub: case Token_Xor: case Token_Not: s = parse_simple_statement(f); if (s->kind != AstNode_ProcedureDeclaration && !allow_token(f, Token_Semicolon)) { ast_file_err(f, f->cursor[0], "Expected `;` after statement, got `%.*s`", LIT(token_strings[f->cursor[0].kind])); } return s; // TODO(bill): other keywords case Token_if: return parse_if_statement(f); case Token_return: return parse_return_statement(f); case Token_for: return parse_for_statement(f); case Token_defer: return parse_defer_statement(f); // case Token_match: return NULL; // TODO(bill): Token_match // case Token_case: return NULL; // TODO(bill): Token_case case Token_break: case Token_continue: case Token_fallthrough: next_token(f); expect_token(f, Token_Semicolon); return make_branch_statement(f, token); case Token_Hash: s = parse_tag_statement(f, NULL); s->tag_statement.statement = parse_statement(f); // TODO(bill): Find out why this doesn't work as an argument return s; case Token_OpenBrace: return parse_block_statement(f); case Token_Semicolon: s = make_empty_statement(f, token); next_token(f); return s; } ast_file_err(f, token, "Expected a statement, got `%.*s`", LIT(token_strings[token.kind])); fix_advance_to_next_statement(f); return make_bad_statement(f, token, f->cursor[0]); } AstNode *parse_statement_list(AstFile *f, isize *list_count_) { AstNode *list_root = NULL; AstNode *list_curr = NULL; isize list_count = 0; while (f->cursor[0].kind != Token_case && f->cursor[0].kind != Token_CloseBrace && f->cursor[0].kind != Token_EOF) { DLIST_APPEND(list_root, list_curr, parse_statement(f)); list_count++; } if (list_count_) *list_count_ = list_count; return list_root; } ParseFileError init_ast_file(AstFile *f, String fullpath) { if (!string_has_extension(fullpath, make_string("odin"))) { gb_printf_err("Only `.odin` files are allowed\n"); return ParseFile_WrongExtension; } TokenizerInitError err = init_tokenizer(&f->tokenizer, fullpath); if (err == TokenizerInit_None) { gb_array_init(f->tokens, gb_heap_allocator()); for (;;) { Token token = tokenizer_get_token(&f->tokenizer); if (token.kind == Token_Invalid) return ParseFile_InvalidToken; gb_array_append(f->tokens, token); if (token.kind == Token_EOF) break; } f->cursor = &f->tokens[0]; // NOTE(bill): Is this big enough or too small? isize arena_size = gb_max(gb_size_of(AstNode), gb_size_of(AstScope)); arena_size *= 2*gb_array_count(f->tokens); gb_arena_init_from_allocator(&f->arena, gb_heap_allocator(), arena_size); open_ast_scope(f); f->file_scope = f->curr_scope; return ParseFile_None; } switch (err) { case TokenizerInit_NotExists: return ParseFile_NotFound; case TokenizerInit_Permission: return ParseFile_Permission; case TokenizerInit_Empty: return ParseFile_EmptyFile; } return ParseFile_InvalidFile; } void destroy_ast_file(AstFile *f) { close_ast_scope(f); gb_arena_free(&f->arena); gb_array_free(f->tokens); gb_free(gb_heap_allocator(), f->tokenizer.fullpath.text); destroy_tokenizer(&f->tokenizer); } b32 init_parser(Parser *p) { gb_array_init(p->files, gb_heap_allocator()); gb_array_init(p->imports, gb_heap_allocator()); return true; } void destroy_parser(Parser *p) { // TODO(bill): Fix memory leak gb_for_array(i, p->files) { destroy_ast_file(&p->files[i]); } #if 1 gb_for_array(i, p->imports) { // gb_free(gb_heap_allocator(), p->imports[i].text); } #endif gb_array_free(p->files); gb_array_free(p->imports); } // NOTE(bill): Returns true if it's added b32 try_add_import_path(Parser *p, String import_file) { gb_for_array(i, p->imports) { String import = p->imports[i]; if (are_strings_equal(import, import_file)) { return false; } } gb_array_append(p->imports, import_file); return true; } gb_global Rune illegal_import_runes[] = { '"', '\'', '`', ' ', '\\', // NOTE(bill): Disallow windows style filepaths '!', '$', '%', '^', '&', '*', '(', ')', '=', '+', '[', ']', '{', '}', ';', ':', '#', '|', ',', '<', '>', '?', }; b32 is_import_path_valid(String path) { if (path.len > 0) { u8 *start = path.text; u8 *end = path.text + path.len; u8 *curr = start; Rune r = -1; while (curr < end) { isize width = 1; r = curr[0]; if (r >= 0x80) { width = gb_utf8_decode(curr, end-curr, &r); if (r == GB_RUNE_INVALID && width == 1) return false; else if (r == GB_RUNE_BOM && curr-start > 0) return false; } for (isize i = 0; i < gb_count_of(illegal_import_runes); i++) { if (r == illegal_import_runes[i]) return false; } curr += width; } return true; } return false; } void parse_file(Parser *p, AstFile *f) { String filepath = f->tokenizer.fullpath; String base_dir = filepath; for (isize i = filepath.len-1; i >= 0; i--) { if (base_dir.text[i] == GB_PATH_SEPARATOR) break; base_dir.len--; } f->declarations = parse_statement_list(f, &f->declaration_count); for (AstNode *node = f->declarations; node != NULL; node = node->next) { if (!is_ast_node_declaration(node) && node->kind != AstNode_BadStatement && node->kind != AstNode_EmptyStatement) { // NOTE(bill): Sanity check ast_file_err(f, ast_node_token(node), "Only declarations are allowed at file scope"); } else { if (node->kind == AstNode_ImportDeclaration) { auto *id = &node->import_declaration; String file = id->filepath.string; String file_str = {}; if (file.text[0] == '"') file_str = make_string(file.text+1, file.len-2); char ext[] = ".odin"; isize ext_len = gb_size_of(ext)-1; b32 append_ext = false; if (!is_import_path_valid(file_str)) { ast_file_err(f, ast_node_token(node), "Invalid import path"); continue; } if (string_extension_position(file_str) < 0) append_ext = true; isize str_len = base_dir.len+file_str.len; if (append_ext) str_len += ext_len; u8 *str = gb_alloc_array(gb_heap_allocator(), u8, str_len+1); defer (gb_free(gb_heap_allocator(), str)); gb_memcopy(str, base_dir.text, base_dir.len); gb_memcopy(str+base_dir.len, file_str.text, file_str.len); if (append_ext) gb_memcopy(str+base_dir.len+file_str.len, ext, ext_len+1); str[str_len] = '\0'; char *path_str = gb_path_get_full_name(gb_heap_allocator(), cast(char *)str); String import_file = make_string(path_str); if (!try_add_import_path(p, import_file)) { gb_free(gb_heap_allocator(), import_file.text); } } } } } ParseFileError parse_files(Parser *p, char *init_filename) { char *fullpath_str = gb_path_get_full_name(gb_heap_allocator(), init_filename); String init_fullpath = make_string(fullpath_str); gb_array_append(p->imports, init_fullpath); gb_for_array(i, p->imports) { String import_path = p->imports[i]; AstFile file = {}; ParseFileError err = init_ast_file(&file, import_path); if (err != ParseFile_None) { gb_printf_err("Failed to parse file: %.*s\n", LIT(import_path)); switch (err) { case ParseFile_WrongExtension: gb_printf_err("\tInvalid file extension\n"); break; case ParseFile_InvalidFile: gb_printf_err("\tInvalid file\n"); break; case ParseFile_EmptyFile: gb_printf_err("\tFile is empty\n"); break; case ParseFile_Permission: gb_printf_err("\tFile permissions problem\n"); break; case ParseFile_NotFound: gb_printf_err("\tFile cannot be found\n"); break; case ParseFile_InvalidToken: gb_printf_err("\tInvalid token found in file\n"); break; } return err; } parse_file(p, &file); gb_array_append(p->files, file); } return ParseFile_None; }