Split the parser from the code generator

Rakefile

@@ -110,7 +110,7 @@ task :backport do
       .gsub(/ & /, ' AND ')
       .gsub(/ -> /, ': ')
       .gsub(/program;/, "MODULE #{module_name};")
-      .gsub(/module;/, "IMPLEMENTATION MODULE #{module_name};")
+      .gsub(/\bmodule;/, "IMPLEMENTATION MODULE #{module_name};")
       .gsub(/end\./, "END #{module_name}.")
       .gsub(/([[:space:]]*)end(;?)$/, '\1END\2')
       .gsub(/^([[:space:]]*)(while|return|if)\b/) { |match| match.upcase }

source/Compiler.elna

@@ -7,6 +7,7 @@ from M2RTS import HALT, ExitOnHalt;
 from Lexer import Lexer, lexer_destroy, lexer_initialize;
 from Transpiler import transpile;
 from CommandLineInterface import PCommandLine, parse_command_line;
+from Parser import PAstModule, parse_module;
 
 var
   command_line: PCommandLine;
@@ -15,6 +16,7 @@ proc compile_from_stream();
 var
   lexer: Lexer;
   source_input: File;
+  ast_module: PAstModule;
 begin
   source_input := OpenToRead(command_line^.input);
 
@@ -29,7 +31,8 @@ begin
   if IsNoError(source_input) then
     lexer_initialize(ADR(lexer), source_input);
 
-    transpile(ADR(lexer), StdOut, command_line^.input);
+    ast_module := parse_module(ADR(lexer));
+    transpile(ast_module, StdOut, command_line^.input);
 
     lexer_destroy(ADR(lexer));
 

source/Lexer.elna

@@ -11,7 +11,7 @@ from MemUtils import MemCopy, MemZero;
 from StrCase import Lower;
 
 const
-  CHUNK_SIZE = 65536;
+  CHUNK_SIZE = 85536;
 
 type
   (*

source/Parser.def

@@ -153,12 +153,12 @@ TYPE
   PAstTypeExpression = POINTER TO AstTypeExpression;
   PPAstTypeExpression = POINTER TO PAstTypeExpression;
 
-  AstTypeDeclaration = RECORD
+  AstTypedDeclaration = RECORD
     identifier: Identifier;
     type_expression: PAstTypeExpression
   END;
-  PAstTypeDeclaration = POINTER TO AstTypeDeclaration;
+  PAstTypedDeclaration = POINTER TO AstTypedDeclaration;
-  PPAstTypeDeclaration = POINTER TO PAstTypeDeclaration;
+  PPAstTypedDeclaration = POINTER TO PAstTypedDeclaration;
 
   AstVariableDeclaration = RECORD
     variable_name: Identifier;
@@ -167,23 +167,38 @@ TYPE
   PAstVariableDeclaration = POINTER TO AstVariableDeclaration;
   PPAstVariableDeclaration = POINTER TO PAstVariableDeclaration;
 
+  AstProcedureDeclaration = RECORD
+    name: Identifier;
+    parameter_count: CARDINAL;
+    parameters: PAstTypedDeclaration;
+    return_type: PAstTypeExpression;
+    constants: PPAstConstantDeclaration;
+    variables: PPAstVariableDeclaration;
+    statements: AstCompoundStatement
+  END;
+  PAstProcedureDeclaration = POINTER TO AstProcedureDeclaration;
+  PPAstProcedureDeclaration = POINTER TO PAstProcedureDeclaration;
+
   AstModule = RECORD
+    main: BOOLEAN;
     imports: PPAstImportStatement;
     constants: PPAstConstantDeclaration;
-    types: PPAstTypeDeclaration;
+    types: PPAstTypedDeclaration;
-    variables: PPAstVariableDeclaration
+    variables: PPAstVariableDeclaration;
+    procedures: PPAstProcedureDeclaration;
+    statements: AstCompoundStatement
   END;
   PAstModule = POINTER TO AstModule;
 
 PROCEDURE parse_type_expression(lexer: PLexer): PAstTypeExpression;
-PROCEDURE parse_type_part(lexer: PLexer): PPAstTypeDeclaration;
+PROCEDURE parse_type_part(lexer: PLexer): PPAstTypedDeclaration;
 PROCEDURE parse_variable_part(lexer: PLexer): PPAstVariableDeclaration;
 PROCEDURE parse_constant_part(lexer: PLexer): PPAstConstantDeclaration;
 PROCEDURE parse_import_part(lexer: PLexer): PPAstImportStatement;
 PROCEDURE parse_designator(lexer: PLexer): PAstExpression;
 PROCEDURE parse_expression(lexer: PLexer): PAstExpression;
-PROCEDURE parse_return_statement(lexer: PLexer): PAstStatement;
+PROCEDURE parse_statement_part(lexer: PLexer): AstCompoundStatement;
-PROCEDURE parse_assignment_statement(lexer: PLexer; assignee: PAstExpression): PAstStatement;
+PROCEDURE parse_procedure_part(lexer: PLexer): PPAstProcedureDeclaration;
-PROCEDURE parse_call_statement(lexer: PLexer; call: PAstExpression): PAstStatement;
+PROCEDURE parse_module(lexer: PLexer): PAstModule;
 
 END Parser.

source/Parser.elna

@@ -109,7 +109,7 @@ begin
 
     result^.length := token.integerKind;
 
-    token := transpiler_lex(lexer);
+    token := transpiler_lex(lexer)
   end;
   token := transpiler_lex(lexer);
   result^.base := parse_type_expression(lexer);
@@ -235,10 +235,10 @@ begin
   return result
 end;
 
-proc parse_type_declaration(lexer: PLexer) -> PAstTypeDeclaration;
+proc parse_type_declaration(lexer: PLexer) -> PAstTypedDeclaration;
 var
   token: LexerToken;
-  result: PAstTypeDeclaration;
+  result: PAstTypedDeclaration;
 begin
   token := lexer_current(lexer);
 
@@ -254,16 +254,16 @@ begin
   return result
 end;
 
-proc parse_type_part(lexer: PLexer) -> PPAstTypeDeclaration;
+proc parse_type_part(lexer: PLexer) -> PPAstTypedDeclaration;
 var
   token: LexerToken;
-  result: PPAstTypeDeclaration;
+  result: PPAstTypedDeclaration;
-  current_declaration: PPAstTypeDeclaration;
+  current_declaration: PPAstTypedDeclaration;
   declaration_count: CARDINAL;
 begin
   token := lexer_current(lexer);
 
-  ALLOCATE(result, TSIZE(PAstTypeDeclaration));
+  ALLOCATE(result, TSIZE(PAstTypedDeclaration));
   current_declaration := result;
   declaration_count := 0;
 
@@ -273,16 +273,16 @@ begin
     while token.kind = lexerKindIdentifier do
       INC(declaration_count);
 
-      REALLOCATE(result, TSIZE(PAstTypeDeclaration) * (declaration_count + 1));
+      REALLOCATE(result, TSIZE(PAstTypedDeclaration) * (declaration_count + 1));
       current_declaration := result;
-      INC(current_declaration, TSIZE(PAstTypeDeclaration) * (declaration_count - 1));
+      INC(current_declaration, TSIZE(PAstTypedDeclaration) * (declaration_count - 1));
 
       current_declaration^ := parse_type_declaration(lexer);
       token := transpiler_lex(lexer)
     end
   end;
   if declaration_count <> 0 then
-    INC(current_declaration, TSIZE(PAstTypeDeclaration))
+    INC(current_declaration, TSIZE(PAstTypedDeclaration))
   end;
   current_declaration^ := nil;
 
@@ -481,18 +481,18 @@ begin
     NEW(literal);
 
     literal^.kind := astLiteralKindInteger;
-    literal^.integer := token.integerKind;
+    literal^.integer := token.integerKind
   end;
   if (token.kind = lexerKindCharacter) or (token.kind = lexerKindString) then
     NEW(literal);
 
     literal^.kind := astLiteralKindString;
-    literal^.string := token.stringKind;
+    literal^.string := token.stringKind
   end;
   if token.kind = lexerKindNull then
     NEW(literal);
 
-    literal^.kind := astLiteralKindNull;
+    literal^.kind := astLiteralKindNull
   end;
   if token.kind = lexerKindBoolean then
     NEW(literal);
@@ -522,7 +522,7 @@ begin
     NEW(result);
 
     result^.kind := astExpressionKindLiteral;
-    result^.literal := literal;
+    result^.literal := literal
   end;
   if (result = nil) & (next_token.kind = lexerKindMinus) then
     NEW(result);
@@ -658,7 +658,7 @@ begin
     result^.kind := astExpressionKindBinary;
     result^.binary_operator := operator;
     result^.lhs := left;
-    result^.rhs := right;
+    result^.rhs := right
   end;
 
   return result
@@ -757,4 +757,243 @@ begin
   return result
 end;
 
+proc parse_compound_statement(lexer: PLexer) -> AstCompoundStatement;
+var
+  result: AstCompoundStatement;
+  token: LexerToken;
+  current_statement: PPAstStatement;
+  old_count: CARDINAL;
+begin
+  result.count := 0;
+  result.statements := nil;
+
+  token := lexer_current(lexer);
+
+  while token.kind <> lexerKindEnd do
+    old_count := result.count;
+    INC(result.count);
+
+    REALLOCATE(result.statements, TSIZE(PAstStatement) * result.count);
+    current_statement := result.statements;
+
+    INC(current_statement, TSIZE(PAstStatement) * old_count);
+    current_statement^ := parse_statement(lexer);
+
+    token := lexer_current(lexer)
+  end;
+
+  return result
+end;
+
+proc parse_statement(lexer: PLexer) -> PAstStatement;
+var
+  token: LexerToken;
+  statement: PAstStatement;
+  designator: PAstExpression;
+begin
+  statement := nil;
+  token := transpiler_lex(lexer);
+
+  if token.kind = lexerKindIf then
+    statement := parse_if_statement(lexer)
+  end;
+  if token.kind = lexerKindWhile then
+    statement := parse_while_statement(lexer)
+  end;
+  if token.kind = lexerKindReturn then
+    statement := parse_return_statement(lexer)
+  end;
+  if token.kind = lexerKindIdentifier then
+    designator := parse_designator(lexer);
+    token := lexer_current(lexer);
+
+    if token.kind = lexerKindAssignment then
+      statement := parse_assignment_statement(lexer, designator)
+    end;
+    if token.kind <> lexerKindAssignment then
+      statement := parse_call_statement(lexer, designator)
+    end
+  end;
+  return statement
+end;
+
+proc parse_if_statement(lexer: PLexer) -> PAstStatement;
+var
+  token: LexerToken;
+  result: PAstStatement;
+begin
+  NEW(result);
+  result^.kind := astStatementKindIf;
+
+  token := transpiler_lex(lexer);
+  result^.if_condition := parse_expression(lexer);
+  result^.if_branch := parse_compound_statement(lexer);
+
+  token := transpiler_lex(lexer);
+  return result
+end;
+
+proc parse_while_statement(lexer: PLexer) -> PAstStatement;
+var
+  token: LexerToken;
+  result: PAstStatement;
+begin
+  NEW(result);
+  result^.kind := astStatementKindWhile;
+
+  token := transpiler_lex(lexer);
+  result^.while_condition := parse_expression(lexer);
+  result^.while_body := parse_compound_statement(lexer);
+
+  token := transpiler_lex(lexer);
+  return result
+end;
+
+proc parse_statement_part(lexer: PLexer) -> AstCompoundStatement;
+var
+  token: LexerToken;
+  compound: AstCompoundStatement;
+begin
+  compound.count := 0;
+  compound.statements := nil;
+  token := lexer_current(lexer);
+
+  if token.kind = lexerKindBegin then
+    compound := parse_compound_statement(lexer)
+  end;
+
+  return compound
+end;
+
+proc parse_procedure_heading(lexer: PLexer) -> PAstProcedureDeclaration;
+var
+  token: LexerToken;
+  declaration: PAstProcedureDeclaration;
+  parameter_index: CARDINAL;
+  current_parameter: PAstTypedDeclaration;
+begin
+  NEW(declaration);
+
+  token := transpiler_lex(lexer);
+  declaration^.name := token.identifierKind;
+
+  token := transpiler_lex(lexer);
+
+  declaration^.parameters := nil;
+  declaration^.parameter_count := 0;
+
+  token := transpiler_lex(lexer);
+  while token.kind <> lexerKindRightParen do
+    parameter_index := declaration^.parameter_count;
+    INC(declaration^.parameter_count);
+    REALLOCATE(declaration^.parameters, TSIZE(AstTypedDeclaration) * declaration^.parameter_count);
+
+    current_parameter := declaration^.parameters;
+    INC(current_parameter, TSIZE(AstTypedDeclaration) * parameter_index);
+
+    current_parameter^.identifier := token.identifierKind;
+
+    token := transpiler_lex(lexer);
+    token := transpiler_lex(lexer);
+
+    current_parameter^.type_expression := parse_type_expression(lexer);
+
+    token := transpiler_lex(lexer);
+    if token.kind = lexerKindComma then
+      token := transpiler_lex(lexer)
+    end
+  end;
+  token := transpiler_lex(lexer);
+  declaration^.return_type := nil;
+
+  (* Check for the return type and write it. *)
+  if token.kind = lexerKindArrow then
+    token := transpiler_lex(lexer);
+    declaration^.return_type := parse_type_expression(lexer);
+    token := transpiler_lex(lexer)
+  end;
+  token := transpiler_lex(lexer);
+
+  return declaration
+end;
+
+proc parse_procedure_declaration(lexer: PLexer) -> PAstProcedureDeclaration;
+var
+  token: LexerToken;
+  declaration: PAstProcedureDeclaration;
+begin
+  declaration := parse_procedure_heading(lexer);
+
+  declaration^.constants := parse_constant_part(lexer);
+  declaration^.variables := parse_variable_part(lexer);
+  declaration^.statements := parse_statement_part(lexer);
+
+  token := transpiler_lex(lexer);
+  token := transpiler_lex(lexer);
+
+  return declaration
+end;
+
+proc parse_procedure_part(lexer: PLexer) -> PPAstProcedureDeclaration;
+var
+  token: LexerToken;
+  current_declaration: PPAstProcedureDeclaration;
+  result: PPAstProcedureDeclaration;
+  declaration_count: CARDINAL;
+  declaration_index: CARDINAL;
+begin
+  token := lexer_current(lexer);
+  declaration_count := 0;
+  declaration_index := 0;
+
+  ALLOCATE(result, TSIZE(PAstProcedureDeclaration));
+
+  while token.kind = lexerKindProc do
+    INC(declaration_count);
+    REALLOCATE(result, TSIZE(PAstProcedureDeclaration) * (declaration_count + 1));
+    current_declaration := result;
+    INC(current_declaration, TSIZE(PAstProcedureDeclaration) * declaration_index);
+
+    current_declaration^ := parse_procedure_declaration(lexer);
+    token := lexer_current(lexer);
+    declaration_index := declaration_count
+  end;
+  current_declaration := result;
+  INC(current_declaration, TSIZE(PAstProcedureDeclaration) * declaration_index);
+  current_declaration^ := nil;
+
+  return result
+end;
+
+proc parse_module(lexer: PLexer) -> PAstModule;
+var
+  token: LexerToken;
+  result: PAstModule;
+begin
+  NEW(result);
+  token := transpiler_lex(lexer);
+  result^.main := true;
+
+  if token.kind = lexerKindModule then
+    result^.main := false
+  end;
+  token := transpiler_lex(lexer);
+
+  (* Write the module body. *)
+  token := transpiler_lex(lexer);
+
+  result^.imports := parse_import_part(lexer);
+  result^.constants := parse_constant_part(lexer);
+  result^.types := parse_type_part(lexer);
+
+  result^.variables := parse_variable_part(lexer);
+  result^.procedures := parse_procedure_part(lexer);
+  result^.statements := parse_statement_part(lexer);
+
+  token := transpiler_lex(lexer);
+  token := transpiler_lex(lexer);
+
+  return result
+end;
+
 end.

source/Transpiler.def

@@ -4,15 +4,15 @@ FROM FIO IMPORT File;
 
 FROM Common IMPORT ShortString;
 FROM Lexer IMPORT PLexer, Lexer;
+FROM Parser IMPORT PAstModule;
 
 TYPE
   TranspilerContext = RECORD
     input_name: ShortString;
-    output: File;
+    output: File
-    lexer: PLexer
   END;
   PTranspilerContext = POINTER TO TranspilerContext;
 
-PROCEDURE transpile(lexer: PLexer; output: File; input_name: ShortString);
+PROCEDURE transpile(ast_module: PAstModule; output: File; input_name: ShortString);
 
 END Transpiler.

source/Transpiler.elna

@@ -1,6 +1,6 @@
 module;
 
-from FIO import StdErr, WriteNBytes, WriteLine, WriteChar, WriteString;
+from FIO import WriteNBytes, WriteLine, WriteChar, WriteString;
 from SYSTEM import ADR, ADDRESS, TSIZE;
 
 from NumberIO import IntToStr;
@@ -10,13 +10,11 @@ from MemUtils import MemCopy, MemZero;
 from Common import Identifier, PIdentifier, ShortString;
 from Lexer import Lexer, LexerToken, lexer_current, lexer_lex, LexerKind;
 from Parser import AstTypeExpressionKind, AstExpressionKind, AstLiteralKind, AstUnaryOperator, AstBinaryOperator,
-  AstModule, PAstModule, AstExpression, PPAstExpression, PAstExpression, PAstLiteral,
+  AstModule, PAstModule, AstExpression, PPAstExpression, PAstExpression, PAstLiteral, PPAstProcedureDeclaration,
-  PAstConstantDeclaration, PPAstConstantDeclaration, PAstStatement, AstStatementKind,
+  PAstConstantDeclaration, PPAstConstantDeclaration, PPAstStatement, PAstStatement, AstStatementKind,
-  AstTypeDeclaration, PAstTypeDeclaration, PPAstTypeDeclaration,
+  AstTypedDeclaration, PAstTypedDeclaration, PPAstTypedDeclaration, AstCompoundStatement, PAstProcedureDeclaration,
   PAstVariableDeclaration, PPAstVariableDeclaration, PAstImportStatement, PPAstImportStatement,
-  PAstTypeExpression, PPAstTypeExpression, AstFieldDeclaration, PAstFieldDeclaration,
+  PAstTypeExpression, PPAstTypeExpression, AstFieldDeclaration, PAstFieldDeclaration;
-  parse_type_expression, parse_variable_part, parse_type_part, parse_constant_part, parse_import_part,
-  parse_designator, parse_expression, parse_return_statement, parse_assignment_statement, parse_call_statement;
 
 (* Calls lexer_lex() but skips the comments. *)
 proc transpiler_lex(lexer: PLexer) -> LexerToken;
@@ -118,15 +116,11 @@ begin
   end
 end;
 
-proc transpile_module(context: PTranspilerContext) -> PAstModule;
+proc transpile_module(context: PTranspilerContext, result: PAstModule);
 var
   token: LexerToken;
-  result: PAstModule;
 begin
-  NEW(result);
+  if result^.main = false then
-  token := transpiler_lex(context^.lexer);
-
-  if token.kind = lexerKindModule then
     WriteString(context^.output, 'IMPLEMENTATION ')
   end;
   WriteString(context^.output, 'MODULE ');
@@ -134,37 +128,23 @@ begin
   (* Write the module name and end the line with a semicolon and newline. *)
   transpile_module_name(context);
 
-  token := transpiler_lex(context^.lexer);
   write_semicolon(context^.output);
   WriteLine(context^.output);
 
   (* Write the module body. *)
-  token := transpiler_lex(context^.lexer);
 
-  result^.imports := parse_import_part(context^.lexer);
   transpile_import_part(context, result^.imports);
-
-  result^.constants := parse_constant_part(context^.lexer);
   transpile_constant_part(context, result^.constants);
-  result^.types := parse_type_part(context^.lexer);
   transpile_type_part(context, result^.types);
-
-  result^.variables := parse_variable_part(context^.lexer);
   transpile_variable_part(context, result^.variables);
-
+  transpile_procedure_part(context, result^.procedures);
-  transpile_procedure_part(context);
+  transpile_statement_part(context, result^.statements);
-  transpile_statement_part(context);
 
   WriteString(context^.output, 'END ');
   transpile_module_name(context);
 
-  token := transpiler_lex(context^.lexer);
   WriteChar(context^.output, '.');
-
+  WriteLine(context^.output)
-  token := transpiler_lex(context^.lexer);
-  WriteLine(context^.output);
-
-  return result
 end;
 
 proc transpile_type_fields(context: PTranspilerContext, fields: PAstFieldDeclaration);
@@ -301,7 +281,7 @@ begin
   end
 end;
 
-proc transpile_type_declaration(context: PTranspilerContext, declaration: PAstTypeDeclaration);
+proc transpile_type_declaration(context: PTranspilerContext, declaration: PAstTypedDeclaration);
 var
   written_bytes: CARDINAL;
 begin
@@ -314,9 +294,9 @@ begin
   write_semicolon(context^.output)
 end;
 
-proc transpile_type_part(context: PTranspilerContext, declarations: PPAstTypeDeclaration);
+proc transpile_type_part(context: PTranspilerContext, declarations: PPAstTypedDeclaration);
 var
-  current_declaration: PPAstTypeDeclaration;
+  current_declaration: PPAstTypedDeclaration;
 begin
   if declarations^ <> nil then
     WriteString(context^.output, 'TYPE');
@@ -326,7 +306,7 @@ begin
     while current_declaration^ <> nil do
       transpile_type_declaration(context, current_declaration^);
 
-      INC(current_declaration, TSIZE(PAstTypeDeclaration))
+      INC(current_declaration, TSIZE(PAstTypedDeclaration))
     end;
     WriteLine(context^.output)
   end
@@ -363,51 +343,41 @@ begin
   end
 end;
 
-proc transpile_procedure_heading(context: PTranspilerContext) -> LexerToken;
+proc transpile_procedure_heading(context: PTranspilerContext, declaration: PAstProcedureDeclaration);
 var
   token: LexerToken;
-  result: LexerToken;
+  written_bytes: CARDINAL;
-  type_expression: PAstTypeExpression;
+  parameter_index: CARDINAL;
+  current_parameter: PAstTypedDeclaration;
 begin
   WriteString(context^.output, 'PROCEDURE ');
-
+  written_bytes := WriteNBytes(context^.output, ORD(declaration^.name[1]), ADR(declaration^.name[2]));
-  result := transpiler_lex(context^.lexer);
-  write_current(context^.lexer, context^.output);
-
-  token := transpiler_lex(context^.lexer);
   WriteChar(context^.output, '(');
 
-  token := transpiler_lex(context^.lexer);
+  parameter_index := 0;
-  while token.kind <> lexerKindRightParen do
+  current_parameter := declaration^.parameters;
-    write_current(context^.lexer, context^.output);
 
-    token := transpiler_lex(context^.lexer);
+  while parameter_index < declaration^.parameter_count do
+    written_bytes := WriteNBytes(context^.output, ORD(current_parameter^.identifier[1]), ADR(current_parameter^.identifier[2]));
     WriteString(context^.output, ': ');
-    token := transpiler_lex(context^.lexer);
+    transpile_type_expression(context, current_parameter^.type_expression);
 
-    type_expression := parse_type_expression(context^.lexer);
+    INC(parameter_index);
-	transpile_type_expression(context, type_expression);
+    INC(current_parameter, TSIZE(AstTypedDeclaration));
 
-    token := transpiler_lex(context^.lexer);
+    if parameter_index <> declaration^.parameter_count then
-    if (token.kind = lexerKindSemicolon) or (token.kind = lexerKindComma) then
+      WriteString(context^.output, '; ')
-      WriteString(context^.output, '; ');
-      token := transpiler_lex(context^.lexer)
     end
   end;
+
   WriteString(context^.output, ')');
-  token := transpiler_lex(context^.lexer);
 
   (* Check for the return type and write it. *)
-  if token.kind = lexerKindArrow then
+  if declaration^.return_type <> nil then
     WriteString(context^.output, ': ');
-    token := transpiler_lex(context^.lexer);
+    transpile_type_expression(context, declaration^.return_type)
-    write_current(context^.lexer, context^.output);
-    token := transpiler_lex(context^.lexer)
   end;
-  token := transpiler_lex(context^.lexer);
+  write_semicolon(context^.output)
-  write_semicolon(context^.output);
-
-  return result
 end;
 
 proc transpile_unary_operator(context: PTranspilerContext, operator: AstUnaryOperator);
@@ -470,7 +440,7 @@ begin
 
     if literal^.kind = astLiteralKindInteger then
       IntToStr(literal^.integer, 0, buffer);
-      WriteString(context^.output, buffer);
+      WriteString(context^.output, buffer)
     end;
     if literal^.kind = astLiteralKindString then
       WriteString(context^.output, literal^.string)
@@ -501,7 +471,7 @@ begin
   if expression^.kind = astExpressionKindFieldAccess then
     transpile_expression(context, expression^.aggregate);
     WriteChar(context^.output, '.');
-    written_bytes := WriteNBytes(context^.output, ORD(expression^.field[1]), ADR(expression^.field[2]));
+    written_bytes := WriteNBytes(context^.output, ORD(expression^.field[1]), ADR(expression^.field[2]))
   end;
   if expression^.kind = astExpressionKindUnary then
     transpile_unary_operator(context, expression^.unary_operator);
@@ -540,52 +510,34 @@ begin
   end
 end;
 
-proc transpile_if_statement(context: PTranspilerContext) -> PAstStatement;
+proc transpile_if_statement(context: PTranspilerContext, statement: PAstStatement);
 var
   token: LexerToken;
-  result: PAstStatement;
 begin
-  NEW(result);
+  if statement <> nil then
-  result^.kind := astStatementKindIf;
     WriteString(context^.output, '  IF ');
-
+    transpile_expression(context, statement^.if_condition);
-  token := transpiler_lex(context^.lexer);
-  result^.if_condition := parse_expression(context^.lexer);
-
-  transpile_expression(context, result^.if_condition);
-  token := lexer_current(context^.lexer);
 
     WriteString(context^.output, ' THEN');
     WriteLine(context^.output);
-  transpile_statements(context);
-  WriteString(context^.output, '  END');
-  token := transpiler_lex(context^.lexer);
 
-  return result
+    transpile_compound_statement(context, statement^.if_branch);
+    WriteString(context^.output, '  END')
+  end
 end;
 
-proc transpile_while_statement(context: PTranspilerContext) -> PAstStatement;
+proc transpile_while_statement(context: PTranspilerContext, statement: PAstStatement);
 var
   token: LexerToken;
-  result: PAstStatement;
 begin
-  NEW(result);
-  result^.kind := astStatementKindWhile;
   WriteString(context^.output, '  WHILE ');
-
+  transpile_expression(context, statement^.while_condition);
-  token := transpiler_lex(context^.lexer);
-  result^.while_condition := parse_expression(context^.lexer);
-
-  transpile_expression(context, result^.while_condition);
-  token := lexer_current(context^.lexer);
 
   WriteString(context^.output, ' DO');
   WriteLine(context^.output);
-  transpile_statements(context);
-  WriteString(context^.output, '  END');
-  token := transpiler_lex(context^.lexer);
 
-  return result
+  transpile_compound_statement(context, statement^.while_body);
+  WriteString(context^.output, '  END')
 end;
 
 proc transpile_assignment_statement(context: PTranspilerContext, statement: PAstStatement);
@@ -599,108 +551,81 @@ proc transpile_return_statement(context: PTranspilerContext, statement: PAstStat
 begin
   WriteString(context^.output, '  RETURN ');
 
-  transpile_expression(context, statement^.returned);
+  transpile_expression(context, statement^.returned)
 end;
 
-proc transpile_statement(context: PTranspilerContext);
+proc transpile_compound_statement(context: PTranspilerContext, statement: AstCompoundStatement);
 var
-  token: LexerToken;
+  current_statement: PPAstStatement;
-  written_bytes: CARDINAL;
+  index: CARDINAL;
-  statement: PAstStatement;
-  designator: PAstExpression;
 begin
-  token := transpiler_lex(context^.lexer);
+  index := 0;
+  current_statement := statement.statements;
 
-  if token.kind = lexerKindIf then
+  while index < statement.count do
-    statement := transpile_if_statement(context)
+    transpile_statement(context, current_statement^);
-  end;
-  if token.kind = lexerKindWhile then
-    statement := transpile_while_statement(context)
-  end;
-  if token.kind = lexerKindReturn then
-    statement := parse_return_statement(context^.lexer);
-    transpile_return_statement(context, statement)
-  end;
-  if token.kind = lexerKindIdentifier then
-    designator := parse_designator(context^.lexer);
-    token := lexer_current(context^.lexer);
 
-    if token.kind = lexerKindAssignment then
+    INC(current_statement, TSIZE(PAstStatement));
-      statement := parse_assignment_statement(context^.lexer, designator);
+    INC(index);
-      transpile_assignment_statement(context, statement)
-    end;
-    if token.kind <> lexerKindAssignment then
-      statement := parse_call_statement(context^.lexer, designator);
-	  transpile_expression(context, designator);
 
-      written_bytes := WriteNBytes(StdErr, 5, context^.lexer^.start);
+    if index <> statement.count then
-      WriteLine(StdErr);
-    end
-  end
-end;
-
-proc transpile_statements(context: PTranspilerContext);
-var
-  token: LexerToken;
-begin
-  token := lexer_current(context^.lexer);
-
-  while token.kind <> lexerKindEnd do
-    transpile_statement(context);
-    token := lexer_current(context^.lexer);
-
-    if token.kind = lexerKindSemicolon then
       WriteChar(context^.output, ';')
     end;
     WriteLine(context^.output)
   end
 end;
 
-proc transpile_statement_part(context: PTranspilerContext);
+proc transpile_statement(context: PTranspilerContext, statement: PAstStatement);
-var
-  token: LexerToken;
 begin
-  token := lexer_current(context^.lexer);
+  if statement^.kind = astStatementKindIf then
-  if token.kind = lexerKindBegin then
+    transpile_if_statement(context, statement)
-    WriteString(context^.output, 'BEGIN');
+  end;
-    WriteLine(context^.output);
+  if statement^.kind = astStatementKindWhile then
-    transpile_statements(context)
+    transpile_while_statement(context, statement)
+  end;
+  if statement^.kind = astStatementKindReturn then
+    transpile_return_statement(context, statement)
+  end;
+  if statement^.kind = astStatementKindAssignment then
+    transpile_assignment_statement(context, statement)
+  end;
+  if statement^.kind = astStatementKindCall then
+    transpile_expression(context, statement^.call)
   end
 end;
 
-proc transpile_procedure_declaration(context: PTranspilerContext);
+proc transpile_statement_part(context: PTranspilerContext, compound: AstCompoundStatement);
-var
-  token: LexerToken;
-  seen_variables: PPAstVariableDeclaration;
-  written_bytes: CARDINAL;
-  seen_constants: PPAstConstantDeclaration;
 begin
-  token := transpile_procedure_heading(context);
+  if compound.count > 0 then
-  seen_constants := parse_constant_part(context^.lexer);
+    WriteString(context^.output, 'BEGIN');
-  transpile_constant_part(context, seen_constants);
+    WriteLine(context^.output);
-
+    transpile_compound_statement(context, compound)
-  seen_variables := parse_variable_part(context^.lexer);
+  end
-  transpile_variable_part(context, seen_variables);
-  transpile_statement_part(context);
-
-  WriteString(context^.output, 'END ');
-  written_bytes := WriteNBytes(context^.output, ORD(token.identifierKind[1]), ADR(token.identifierKind[2]));
-
-  token := transpiler_lex(context^.lexer);
-  write_semicolon(context^.output);
-  token := transpiler_lex(context^.lexer)
 end;
 
-proc transpile_procedure_part(context: PTranspilerContext);
+proc transpile_procedure_declaration(context: PTranspilerContext, declaration: PAstProcedureDeclaration);
 var
-  token: LexerToken;
+  written_bytes: CARDINAL;
 begin
-  token := lexer_current(context^.lexer);
+  transpile_procedure_heading(context, declaration);
 
-  while token.kind = lexerKindProc do
+  transpile_constant_part(context, declaration^.constants);
-    transpile_procedure_declaration(context);
+  transpile_variable_part(context, declaration^.variables);
-    token := lexer_current(context^.lexer);
+  transpile_statement_part(context, declaration^.statements);
-    WriteLine(context^.output)
+
+  WriteString(context^.output, 'END ');
+  written_bytes := WriteNBytes(context^.output, ORD(declaration^.name[1]), ADR(declaration^.name[2]));
+
+  write_semicolon(context^.output)
+end;
+
+proc transpile_procedure_part(context: PTranspilerContext, declaration: PPAstProcedureDeclaration);
+begin
+  while declaration^ <> nil do
+    transpile_procedure_declaration(context, declaration^);
+    WriteLine(context^.output);
+
+    INC(declaration, TSIZE(PAstProcedureDeclaration))
   end
 end;
 
@@ -728,20 +653,17 @@ begin
   while (context^.input_name[counter] <> '.') & (ORD(context^.input_name[counter]) <> 0) do
     WriteChar(context^.output, context^.input_name[counter]);
     INC(counter)
-  end;
+  end
 end;
 
-proc transpile(lexer: PLexer, output: File, input_name: ShortString);
+proc transpile(ast_module: PAstModule, output: File, input_name: ShortString);
 var
-  token: LexerToken;
   context: TranspilerContext;
-  ast_module: PAstModule;
 begin
   context.input_name := input_name;
   context.output := output;
-  context.lexer := lexer;
 
-  ast_module := transpile_module(ADR(context))
+  transpile_module(ADR(context), ast_module)
 end;
 
 end.