/// <summary>
/// Lee una sentencia if
/// </summary>
private InstructionIf ReadCommandIf(Token token)
{
InstructionIf instruction = new InstructionIf(token);
// Lee la expresión
instruction.Condition = ReadExpression(ExpressionReaderMode.Normal, out string error);
instruction.ConditionRPN = _expressionEvaluator.ConvertToRPN(instruction.Condition);
if (!string.IsNullOrWhiteSpace(error))
{
instruction.Error = error;
}
// Lee el resto de datos
if (!instruction.IsError)
{
Token nextToken = GetToken(true);
// Comprueba si es un error
if (nextToken.Type != Token.TokenType.EndSentenceBlock && nextToken.Type != Token.TokenType.Sentence)
{
instruction.Error = "No se ha encontrado el final de la instrucción";
}
else if (!IsEndCommand(nextToken)) // ... no es un if vacío
{
bool atElse = false;
// Lee las instrucciones de la parte
nextToken = ReadInstructions(instruction.Instructions);
// Comprueba si la siguiente es una sentencia else
if (IsElseCommand(nextToken))
{
// Indica que es un else
atElse = true;
// Quita los tokens del else
if (nextToken.Type == Token.TokenType.StartSentenceBlock)
{
GetToken();
nextToken = GetToken(true);
}
if (nextToken.Type == Token.TokenType.Sentence && nextToken.Content.Equals("else", StringComparison.CurrentCultureIgnoreCase))
{
GetToken();
nextToken = GetToken(true);
}
if (nextToken.Type == Token.TokenType.EndSentenceBlock)
{
GetToken();
nextToken = GetToken(true);
}
}
// Lee la parte else
if (atElse)
{
ReadInstructions(instruction.InstructionsElse);
}
}
}
// Devuelve la instrucción
return(instruction);
}
public override Instruction Read(ExtendedBinaryReader reader)
{
var instruction = new InstructionIf();
short amount = reader.ReadInt16();
instruction.Arguments.Add(reader.ReadInt32());
for (int i = 0; i < amount; ++i)
{
uint left = reader.ReadUInt32();
uint right = reader.ReadUInt32();
var compareOp = (Comparison.ComparisonOperators)reader.ReadByte();
instruction.Comparisons.Add(new Comparison(left, compareOp, right));
}
return(instruction);
}
/// <summary>
/// Ejecuta una instrucción if
/// </summary>
private void Execute(InstructionIf instruction)
{
ValueBase result = ExpressionComputer.Evaluate(instruction.ConditionRPN);
if (result.HasError)
{
Compiler.LocalErrors.Add(instruction.Token, result.Error);
}
else if (!(result is ValueBool))
{
Compiler.LocalErrors.Add(instruction.Token, "El resultado de calcular la expresión no es un valor lógico");
}
else if ((result as ValueBool).Value)
{
Execute(instruction.Instructions);
}
else
{
Execute(instruction.InstructionsElse);
}
}