public static JsObject EvalIf(JsExpression x, Env env)
{
JsBool cond = (JsBool)(x.child[0].evaluate(env));
if (x.child.Count == 3)
{
return(cond ? x.child[1].evaluate(env) : x.child[2].evaluate(env));
}
else
{
return(cond ? x.child[1].evaluate(env) : new JsBool(false));
}
}
public static JsObject EvalWhile(JsExpression x, Env env)
{
JsBool cond = (JsBool)(x.child[0].evaluate(env));
JsObject res = null;
if (cond)
{
while ((JsBool)x.child[0].evaluate(env))//build-in
{
res = x.child[1].evaluate(env);
}
}
return(res);
}
public static JsBool BoolEval(this JsExpression[] args, Env env, Func <JsBool, JsBool, bool> rel)
{
(args.Length > 1).OrThrows("arguments are too less in relation expressions");
JsBool curr = (JsBool)args[0].evaluate(env);
foreach (var item in args.Skip(1))
{
JsBool next = (JsBool)item.evaluate(env);
if (rel(curr, next))
{
curr = next;
}
else
{
return(JsBool.False);
}
}
return(JsBool.True);
}