// This code executes all statements in a list.

Statements {
  traversal doStatements (StatementVisitor) {
    bypassing Statements
    to {Statement, PrintStr, PrintExp, PrintStrExp} ;
  }
}


StatementVisitor  {

  before Assignment {{
    String name = host.get_varname().toString();
    Symbol sym = Main.symbolTable.findSymbol(name);
    if (sym == null) {
      System.out.println ("Error: undefined variable " + name);
      Main.stopSimulation = true;
    } else {
      Double val = host.get_expr().evaluate();
      sym.set_value (Value.parse(""+val)); 
    }
  }}

  before PrintStr {{
    System.out.println (host.get_string());
  }}

  before PrintStrExp {{
    System.out.print (host.get_string());
    System.out.println (host.get_expr().evaluate());
  }}

  before PrintExp {{
    System.out.println (host.get_expr().evaluate());
  }}

  before Stop {{
    Main.stopSimulation = true;
  }}

  before Dump {{
    Main.symbolTable.allSymbols(new DumpSymbolTableVisitor());
  }}

  before If_Then {{
    Double val = host.get_expr().evaluate();
    if (val.doubleValue() != 0.0) {
      // do "then" part
      host.get_thenStmts().doStatements(new StatementVisitor());
    } else {
      // do "else" part
      Statements elseStmts = host.get_elseStmts();
      if (elseStmts != null) {
        elseStmts.doStatements(new StatementVisitor());
      }
    }
  }}

  before While {{
    while (true) {
      Double val = host.get_expr().evaluate();
      if (val.doubleValue() == 0.0) {
        return;
      }
      host.get_statements().doStatements(new StatementVisitor());
    }
  }}
}