public void If()
{
ILispEnvironment environment = new GlobalEnvironment();
environment.Set(new Symbol("kablooey"), new NativeLambda {
Body = parameters => { throw new LispException("kablooey!"); }
});
// Ensure only the "then" clause is evaluated on a true condition.
LispAssert.EvaluatesTo(Lisp.Constant(1),
Lisp.List(Lisp.Symbol("if"), Lisp.Constant(true), Lisp.Constant(1), Lisp.List(Lisp.Symbol("kablooey"))),
environment);
LispAssert.ThrowsWhenEvaluated(
Lisp.List(Lisp.Symbol("if"), Lisp.Constant(true), Lisp.List(Lisp.Symbol("kablooey")), Lisp.Constant(1)),
environment);
// Ensure only the "else" clause is evaluated on a false condition.
LispAssert.EvaluatesTo(Lisp.Constant(1),
Lisp.List(Lisp.Symbol("if"), Lisp.Constant(false), Lisp.List(Lisp.Symbol("kablooey")), Lisp.Constant(1)),
environment);
LispAssert.ThrowsWhenEvaluated(
Lisp.List(Lisp.Symbol("if"), Lisp.Constant(false), Lisp.Constant(1), Lisp.List(Lisp.Symbol("kablooey"))),
environment);
// Ensure the test condition clause is evaluated. In this case, a non-empty list would be true if not
// evaluated, but evaluating the expression will produce false.
LispAssert.EvaluatesTo(Lisp.Constant(2),
Lisp.List(Lisp.Symbol("if"), Lisp.List(Lisp.Symbol("number?"), Lisp.Symbol("car")), Lisp.Constant(1), Lisp.Constant(2)));
// Test truth / falsiness of non-boolean - only #f and () should count as false.
LispAssert.EvaluatesTo(Lisp.Constant(2), Lisp.List(Lisp.Symbol("if"), Lisp.Nil, Lisp.Constant(1), Lisp.Constant(2)));
LispAssert.EvaluatesTo(Lisp.Constant(1), Lisp.List(Lisp.Symbol("if"), Lisp.Quote(Lisp.List(Lisp.Constant(false))), Lisp.Constant(1), Lisp.Constant(2)));
LispAssert.EvaluatesTo(Lisp.Constant(1), Lisp.List(Lisp.Symbol("if"), Lisp.Constant(""), Lisp.Constant(1), Lisp.Constant(2)));
LispAssert.EvaluatesTo(Lisp.Constant(1), Lisp.List(Lisp.Symbol("if"), Lisp.Symbol("cdr"), Lisp.Constant(1), Lisp.Constant(2)));
}
public void MakeString()
{
LispAssert.EvaluatesTo(Lisp.Constant("xxxxxxxxxx"),
Lisp.List(Lisp.Symbol("make-string"), Lisp.Constant(10), Lisp.Constant('x')));
LispAssert.ThrowsWhenEvaluated(
Lisp.List(Lisp.Symbol("make-string"), Lisp.Constant(9.3m), Lisp.Constant('x')));
LispAssert.EvaluatesTo(Lisp.Constant(8),
Lisp.List(Lisp.Symbol("string-length"), Lisp.List(Lisp.Symbol("make-string"), Lisp.Constant(8))));
}
public void StringRef()
{
LispAssert.EvaluatesTo(Lisp.Constant('t'),
Lisp.List(Lisp.Symbol("string-ref"), Lisp.Constant("test"), Lisp.Constant(0)));
LispAssert.EvaluatesTo(Lisp.Constant('s'),
Lisp.List(Lisp.Symbol("string-ref"), Lisp.Constant("test test test"), Lisp.Constant(12)));
LispAssert.ThrowsWhenEvaluated(
Lisp.List(Lisp.Symbol("string-ref"), Lisp.Constant("test"), Lisp.Constant(-1)));
LispAssert.ThrowsWhenEvaluated(
Lisp.List(Lisp.Symbol("string-ref"), Lisp.Constant("test"), Lisp.Constant(4)));
LispAssert.ThrowsWhenEvaluated(
Lisp.List(Lisp.Symbol("string-ref"), Lisp.Constant("test"), Lisp.Constant(2.2m)));
}
public void Cdr()
{
LispAssert.EvaluatesTo(Lisp.List(Lisp.Constant(2), Lisp.Constant(3)),
Lisp.List(Lisp.Symbol("cdr"), Lisp.Quote(Lisp.List(Lisp.Constant(1), Lisp.Constant(2), Lisp.Constant(3)))));
LispAssert.EvaluatesTo(Lisp.Nil,
Lisp.List(Lisp.Symbol("cdr"), Lisp.Quote(Lisp.List(Lisp.Constant(1)))));
LispAssert.EvaluatesTo(Lisp.Constant(2),
Lisp.List(Lisp.Symbol("cdr"), Lisp.Quote(Lisp.Cons(Lisp.Constant(1), Lisp.Constant(2)))));
LispAssert.ThrowsWhenEvaluated(Lisp.List(Lisp.Symbol("cdr"), Lisp.Nil));
LispAssert.ThrowsWhenEvaluated <TypeMismatchException>(Lisp.List(Lisp.Symbol("cdr"), Lisp.Constant(3)));
LispAssert.ThrowsWhenEvaluated <SignatureMismatchException>(Lisp.List(Lisp.Symbol("cdr")));
}