public static object?Sub(MyArgs args)
{
var that = args.That;
var start = MyNumber.TryConvertFrom(args[0]);
var len = MyNumber.TryConvertFrom(args[1]);
if (that is string str && start is not null)
{
if (str.Length == 0)
{
return("");
}
int s = (int)start;
s = (s % str.Length + str.Length) % str.Length;
if (len is null)
{
return(str.Substring(s));
}
else
{
return(str.Substring(s, (int)len));
}
}
return(null);
}
public static object?ConvertFromMSToCS(object?obj, Type target_type)
{
if (obj is null)
{
return(null);// 注意值类型的情况
}
if (target_type.IsInstanceOfType(obj))
{
return(obj);
}
// @om 一些特殊处理
// Enum
if (target_type.IsEnum)
{
if (obj is string str)
{
return(Enum.Parse(target_type, str));// will three exception
}
var n = MyNumber.TryConvertFrom(obj);
if (n is not null && n.IsInt64)
{
long d = (long)n;// 经过阅读源码，这个是内部最终也会转换过来的版本
return(Enum.ToObject(target_type, d));
}
else
{
return(null);
}
}
public object?Get(object key)
{
MyNumber?num = MyNumber.TryConvertFrom(key);
if (num is not null)
{
if (num.IsInt32)
{
return(this[(int)num]);
}
}
throw new NotImplementedException();
}
/// <summary>
/// MyScript内部使用的比较函数，可以用于支持 a <> b。
/// 1. 字符串，按UTF-16二进制方式比较
/// 2. 数字，正常比较，不过最小的是NaN。
/// 3. 其他的就有些随意了
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns></returns>
public static int Compare(object?a, object?b)
{
if (a == b)
{
return(0);
}
if (a == null)
{
return(-1);
}
if (b == null)
{
return(1);
}
if (a is string sa && b is string sb)
{
return(string.Compare(sa, sb, StringComparison.Ordinal));
}
// 需要对数字类型的特殊处理下
var fa = MyNumber.TryConvertFrom(a);
var fb = MyNumber.TryConvertFrom(b);
if (fa is not null && fb is not null)
{
return(fa.CompareTo(fb));
}
if (a.Equals(b))
{
return(0); // 相等比较特殊处理下吧
}
// 不能使用直接使用 IComparable。大部分实现，遇到类型不一样，会抛异常。
var ta = a.GetType();
var tb = b.GetType();
if (ta == tb)
{
if (a is IComparable ia)
{
return(ia.CompareTo(b));
}
}
// 没办法了，随便比较下啦。选择HashCode，速度可能快些。用FullName也许会更稳定些。
// @om C# 的HashCode的实现方法还为找到确定位置，疑似发现一个，太复杂了点。
return(ta.GetHashCode().CompareTo(tb.GetHashCode()));
}
/// <summary>
/// 等性比较，非常重要。和Compare不一样，Compare == 0, 不一定相等。
/// 1. 数字类型特殊处理
/// </summary>
public static bool CheckEquals(object?a, object?b)
{
if (a == b)
{
return(true);
}
if (a == null || b == null)
{
return(false);
}
// 需要对数字类型的特殊处理下
var fa = MyNumber.TryConvertFrom(a);
var fb = MyNumber.TryConvertFrom(b);
if (fa is not null && fb is not null)
{
return(fa.Equals(fb));
}
public static object?Get(string str, object key)
{
if (key is string ss)
{
if (s_func_map.TryGetValue(ss, out ICall? func))
{
return(func);
}
switch (ss)
{
case "size":
return(ss.Length);
}
return(null);
}
var num = MyNumber.TryConvertFrom(key);
if (num is not null && num.IsInt32)
{
return(str.GetByIdx((int)num));
}
return(null);
}
public MyNumber GetNumber(Frame frame)
{
var x = GetResult(frame);
return(MyNumber.ForceConvertFrom(x));
}
protected override object?_GetResults(Frame frame)
{
object?ret = null;
if (op.Match(Keyword.AND))
{
ret = left.GetBool(frame) && right.GetBool(frame);
}
else if (op.Match(Keyword.OR))
{
ret = left.GetBool(frame) || right.GetBool(frame);
}
else if (op.Match('+'))
{
ret = left.GetNumber(frame) + right.GetNumber(frame);
}
else if (op.Match('-'))
{
ret = left.GetNumber(frame) - right.GetNumber(frame);
}
else if (op.Match('*'))
{
ret = left.GetNumber(frame) * right.GetNumber(frame);
}
else if (op.Match('/'))
{
ret = left.GetNumber(frame) / right.GetNumber(frame);
}
else if (op.Match('%'))
{
ret = left.GetNumber(frame) % right.GetNumber(frame);
}
else if (op.Match(TokenType.DIVIDE))
{
ret = MyNumber.IntegerDivide(left.GetNumber(frame), right.GetNumber(frame));
}
else if (op.Match('^'))
{
ret = MyNumber.Pow(left.GetNumber(frame), right.GetNumber(frame));
}
else if (op.Match('<'))
{
ret = Utils.Compare(left.GetResult(frame), right.GetResult(frame)) < 0;
}
else if (op.Match('>'))
{
ret = Utils.Compare(left.GetResult(frame), right.GetResult(frame)) > 0;
}
else if (op.Match(TokenType.LE))
{
ret = Utils.Compare(left.GetResult(frame), right.GetResult(frame)) <= 0;
}
else if (op.Match(TokenType.GE))
{
ret = Utils.Compare(left.GetResult(frame), right.GetResult(frame)) >= 0;
}
else if (op.Match(TokenType.EQ))
{
ret = Utils.CheckEquals(left.GetResult(frame), right.GetResult(frame));
}
else if (op.Match(TokenType.NE))
{
ret = !Utils.CheckEquals(left.GetResult(frame), right.GetResult(frame));
}
else if (op.Match(TokenType.THREE_CMP))
{
ret = Utils.Compare(left.GetResult(frame), right.GetResult(frame));
}
else if (op.Match(TokenType.CONCAT))
{
ret = left.GetString(frame) + right.GetString(frame);
}
else
{
Debug.Assert(false);
}
return(ret);
}