private static NumExpr Minus(List <Expr> args, Dictionary <string, Expr> env)
{
Expr arg;
int len = args.Count;
if (len < 1)
{
throw new EvaluatorException(String.Format("the expected number of arguments does not match the given number{0} expected: at least 1", "\n"));
}
arg = args[0];
Expr res = arg.eval(env);
if (res.GetType() != typeof(NumExpr))
{
throw new EvaluatorException("expected number?");
}
NumExpr res_num = (NumExpr)res;
long f_num = res_num.getValue();
if (len == 1)
{
return(new NumExpr(-1 * f_num));
}
long sum = f_num;
for (int i = 1; i < len; i++)
{
arg = args[i];
res = arg.eval(env);
if (res.GetType() != typeof(NumExpr))
{
throw new EvaluatorException("expected number?");
}
res_num = (NumExpr)res;
sum = sum - res_num.getValue();
}
return(new NumExpr(sum));
}
private static BoolExpr GreaterThanEqual(List <Expr> args, Dictionary <string, Expr> env)
{
int len = args.Count;
if (len < 2)
{
throw new EvaluatorException(String.Format("the expected number of arguments does not match the given number{0} expected: at least 2", "\n"));
}
Expr first = args[0].eval(env);
if (first.GetType() != typeof(NumExpr))
{
throw new EvaluatorException("expected number?");
}
NumExpr num_f = (NumExpr)first;
long min = num_f.getValue();
Expr arg;
for (int i = 1; i < len; i++)
{
arg = args[i].eval(env);
if (arg.GetType() != typeof(NumExpr))
{
throw new EvaluatorException("expected number?");
}
num_f = (NumExpr)arg;
long num = num_f.getValue();
if (num > min)
{
return(new BoolExpr(false));
}
min = num;
}
return(new BoolExpr(true));
}
private static NumExpr Division(List <Expr> args, Dictionary <string, Expr> env)
{
int len = args.Count;
if (len < 1)
{
throw new EvaluatorException(String.Format("the expected number of arguments does not match the given number{0} expected: at least 1", "\n"));
}
Expr f;
f = args[0].eval(env);
if (f.GetType() != typeof(NumExpr))
{
throw new EvaluatorException("expected number?");
}
NumExpr num_f = (NumExpr)f;
long num = num_f.getValue();
if (len == 1)
{
if (num == 0)
{
throw new EvaluatorException("divide by zero");
}
return(new NumExpr(1 / num));
}
Expr arg;
NumExpr n;
long res = num;
for (int i = 1; i < len; i++)
{
arg = args[i].eval(env);
if (arg.GetType() != typeof(NumExpr))
{
throw new EvaluatorException("expected number?");
}
n = (NumExpr)arg;
res = res / n.getValue();
}
return(new NumExpr(res));
}
private static NumExpr Modulo(List <Expr> args, Dictionary <string, Expr> env)
{
int len = args.Count;
if (len != 2)
{
throw new EvaluatorException(String.Format("the expected number of arguments does not match the given number{0} expected: 2", "\n"));
}
Expr res1 = args[0].eval(env);
Expr res2 = args[1].eval(env);
if (res1.GetType() != typeof(NumExpr) || res2.GetType() != typeof(NumExpr))
{
throw new EvaluatorException("expected number?");
}
NumExpr num_res1 = (NumExpr)res1;
NumExpr num_res2 = (NumExpr)res2;
return(new NumExpr(num_res1.getValue() % num_res2.getValue()));
}
private static NumExpr Plus(List <Expr> args, Dictionary <string, Expr> env)
{
Expr arg;
Expr res;
int len = args.Count;
Int64 sum = 0;
for (int i = 0; i < len; i++)
{
arg = args[i];
res = arg.eval(env);
if (res.GetType() != typeof(NumExpr))
{
throw new EvaluatorException("expected number?");
}
NumExpr num_res = (NumExpr)res;
sum = sum + num_res.getValue();
}
return(new NumExpr(sum));
}