public void HasVariablesWithVariable()
{
Variable variable = new Variable("X");
MatchExpression expr = new MatchExpression(new VariableExpression(variable), new ConstantExpression(123));
Assert.IsTrue(expr.HasVariable());
}
public void MatchOneAtomAndTwoVariablesInTupleWithConcreteTuple()
{
Context context = new Context();
Atom p = new Atom("point");
Variable x = new Variable("X");
Variable y = new Variable("Y");
MatchExpression expr = new MatchExpression(new TupleExpression(new IExpression[] { new AtomExpression(p), new VariableExpression(x), new VariableExpression(y) }), new TupleExpression(new IExpression[] { new AtomExpression(new Atom("point")), new ConstantExpression(1), new ConstantExpression(2) }));
expr.Evaluate(context);
var result1 = context.GetValue("X");
var result2 = context.GetValue("Y");
Assert.IsNotNull(result1);
Assert.AreEqual(1, result1);
Assert.IsNotNull(result2);
Assert.AreEqual(2, result2);
}
public void MatchTwoVariablesWithList()
{
Context context = new Context();
Variable headvar = new Variable("H");
Variable tailvar = new Variable("T");
var list = new List(headvar, tailvar);
var list2 = new List(1, new List(2, new List(3, null)));
MatchExpression expr = new MatchExpression(new ConstantExpression(list), new ConstantExpression(list2));
expr.Evaluate(context);
var result1 = context.GetValue("H");
var result2 = context.GetValue("T");
Assert.IsNotNull(result1);
Assert.AreEqual(1, result1);
Assert.IsNotNull(result2);
Assert.IsInstanceOfType(result2, typeof(List));
Assert.AreEqual("[2,3]", result2.ToString());
}
public void MatchIntegers()
{
MatchExpression expr = new MatchExpression(new ConstantExpression(123), new ConstantExpression(123));
Assert.AreEqual(123, expr.Evaluate(null));
}
public void HasVariablesWithIntegers()
{
MatchExpression expr = new MatchExpression(new ConstantExpression(123), new ConstantExpression(123));
Assert.IsFalse(expr.HasVariable());
}
public void RaiseIfMatchVariableInTupleWithTwoDifferentValues()
{
Context context = new Context();
Variable x = new Variable("X");
MatchExpression expr = new MatchExpression(new TupleExpression(new IExpression[] { new VariableExpression(x), new VariableExpression(x) }), new TupleExpression(new IExpression[] { new ConstantExpression(1), new ConstantExpression(2) }));
try
{
expr.Evaluate(context);
Assert.Fail();
}
catch (Exception ex)
{
Assert.IsInstanceOfType(ex, typeof(InvalidOperationException));
Assert.AreEqual("no match of right hand side value {1,2}", ex.Message);
}
}
public void RaiseIfMatchBoundVariableWithInteger()
{
Context context = new Context();
Variable variable = new Variable("X");
context.SetValue("X", 1);
MatchExpression expr = new MatchExpression(new VariableExpression(variable), new ConstantExpression(123));
try
{
expr.Evaluate(context);
Assert.Fail();
}
catch (Exception ex)
{
Assert.IsInstanceOfType(ex, typeof(InvalidOperationException));
Assert.AreEqual("no match of right hand side value 123", ex.Message);
}
}
public void NoMatchWithException()
{
MatchExpression expr = new MatchExpression(new ConstantExpression(123), new ConstantExpression("foo"));
try
{
expr.Evaluate(null);
Assert.Fail();
}
catch (Exception ex)
{
Assert.IsInstanceOfType(ex, typeof(InvalidOperationException));
Assert.AreEqual("no match of right hand side value foo", ex.Message);
}
}
public void MatchVariableWithInteger()
{
Context context = new Context();
Variable variable = new Variable("X");
MatchExpression expr = new MatchExpression(new VariableExpression(variable), new ConstantExpression(123));
Assert.AreEqual(123, expr.Evaluate(context));
Assert.AreEqual(123, context.GetValue("X"));
}
private IExpression ParseMatchExpression()
{
IExpression expression = this.ParseSimpleExpression();
Token token = this.NextToken();
if (expression == null)
if (token == null)
return null;
else
throw new ParserException(string.Format("Unexpected '{0}'", token.Value));
if (token != null && token.Type == TokenType.Operator && token.Value == "=")
{
expression = new MatchExpression(expression, this.ParseSimpleExpression());
return expression;
}
else if (token != null && token.Type == TokenType.Operator && token.Value == "!")
{
expression = new SendExpression(expression, this.ParseSimpleExpression());
return expression;
}
else
this.PushToken(token);
return expression;
}