public Token([NotNull] string expr, IEnumerable <IToken> tokens, TokenType type)
{
ArgChk.NotNull(expr, nameof(expr));
Expr = expr;
Type = type;
Children = tokens?.ToList();
}
public Token([NotNull] string expr, TokenType type)
{
ArgChk.NotNull(expr, nameof(expr));
Expr = expr;
Type = type;
Children = null;
}
internal Expr([NotNull] IToken root, [NotNull] IExprContext context)
{
ArgChk.NotNull(root, nameof(root));
ArgChk.NotNull(context, nameof(context));
_root = root;
_context = context;
FuncNames = new HashSet <string>(GetFunctionName(_root));
VarNames = new HashSet <string>(GetVariableName(_root));
}
internal IConvertible EvalToken([NotNull] IToken token)
{
ArgChk.NotNull(token, nameof(token));
switch (token.Type)
{
case TokenType.LiteralNumber:
{
ArgChk.NullOrEmpty(token.Children, nameof(token.Children));
return(double.Parse(token.Expr));
}
case TokenType.Identifier:
{
ArgChk.NullOrEmpty(token.Children, nameof(token.Children));
return(_context.GetVar(token.Expr)(_context));
}
case TokenType.Func:
{
// parse child argument
var args = new List <IConvertible>();
if (token.Children?.Any() ?? false)
{
var arg = new Queue <IToken>(token.Children);
while (arg.Count > 0)
{
var curArg = arg.Dequeue();
if (curArg.Type != TokenType.FuncArgs)
{
args.Add(EvalToken(curArg));
}
else
{
ArgChk.NotNullOrEmpty(curArg.Children, nameof(curArg.Children));
foreach (var c in curArg.Children)
{
arg.Enqueue(c);
}
}
}
}
return(_context.GetFunc(token.Expr)(_context, args));
}
case TokenType.FuncArgs:
throw new Sprache.ParseException("unexpected comma");
case TokenType.UnaryPlus:
case TokenType.UnaryNoOp:
{
ExpectArgSize(token.Type.ToString(), token.Children, 1);
return(Arg(token, 0));
}
case TokenType.UnaryMinus:
{
ExpectArgSize(token.Type.ToString(), token.Children, 1);
return(-ArgDouble(token, 0));
}
case TokenType.UnaryNot:
{
ExpectArgSize(token.Type.ToString(), token.Children, 1);
return(!ArgBool(token, 0));
}
case TokenType.BinaryPow:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(Math.Pow(ArgDouble(token, 0), ArgDouble(token, 1)));
}
case TokenType.BinaryMul:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
var arg0 = ArgDouble(token, 0);
// short circuit!!
if (_context.DoubleNearZero(arg0))
{
return(0);
}
return(arg0 * ArgDouble(token, 1));
}
case TokenType.BinaryDiv:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgDouble(token, 0) / ArgDouble(token, 1));
}
case TokenType.BinaryDivInt:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
var arg1 = ArgInteger(token, 1);
var arg0 = ArgInteger(token, 0);
if (arg1 == 0)
{
return((double)arg0 / arg1);
}
return(ArgInteger(token, 0) / arg1);
}
case TokenType.BinaryPlus:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgDouble(token, 0) + ArgDouble(token, 1));
}
case TokenType.BinaryMinus:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgDouble(token, 0) - ArgDouble(token, 1));
}
case TokenType.BinaryLt:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgDouble(token, 0) < ArgDouble(token, 1));
}
case TokenType.BinaryLe:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgDouble(token, 0) <= ArgDouble(token, 1));
}
case TokenType.BinaryGt:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgDouble(token, 0) > ArgDouble(token, 1));
}
case TokenType.BinaryGe:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgDouble(token, 0) >= ArgDouble(token, 1));
}
case TokenType.BinaryEq:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(_context.DoubleNearZero(ArgDouble(token, 0) - ArgDouble(token, 1)));
}
case TokenType.BinaryNe:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(!_context.DoubleNearZero(ArgDouble(token, 0) - ArgDouble(token, 1)));
}
case TokenType.BinaryAnd:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgBool(token, 0) && ArgBool(token, 1));
}
case TokenType.BinaryOr:
{
ExpectArgSize(token.Type.ToString(), token.Children, 2);
return(ArgBool(token, 0) || ArgBool(token, 1));
}
case TokenType.TrinayCondition:
{
ExpectArgSize(token.Type.ToString(), token.Children, 3);
return(ArgBool(token, 0) ? Arg(token, 1) : Arg(token, 2));
}
default:
throw new ArgumentOutOfRangeException();
}
}
internal IConvertible Arg([NotNull] IToken token, int idx)
{
ArgChk.NotNull(token, nameof(token));
ArgChk.InBound(idx, nameof(idx), token.Children);
return(EvalToken(token.Children[idx]));
}
public void TestNotNull()
{
Assert.DoesNotThrow(() => ArgChk.NotNull(0, ArgName));
Assert.Throws <ArgumentNullException>(() => ArgChk.NotNull(_nullObj, ArgName));
Assert.Throws <ArgumentNullException>(() => ArgChk.NotNull(_nullInt, ArgName));
}