public FuncValue(NestedEnv env, string[] ps, IASTNode body)
{
Env = env;
Params = ps;
ParamTypes = null;
Body = body;
}
public FuncValue(NestedEnv env, string[] @params, string[] paramTypes, IASTNode[] defaults, IASTNode body)
{
Env = env;
Params = @params;
ParamTypes = paramTypes;
Defaults = defaults;
Body = body;
}
public override Value Invoke(Value[] args)
{
NestedEnv env = new NestedEnv(Env);
if (CheckAndFill(args, Params, ParamTypes, Defaults, env, false, out string err))
{
return(Body.GetValue(null, env));
}
else
{
Value r = NilValue.Nil;
r["err"] = new StringValue(err);
return(r);
}
}
public NestedEnv()
{
Parent = null;
}
public NestedEnv(NestedEnv parent)
{
Parent = parent;
}
public Value SetValue(Value baseValue, NestedEnv env, Value value) => NilValue.Nil;
public Value GetValue(Value baseValue, NestedEnv env) => Body(env);
public static bool CheckAndFill(Value[] args, string[] ps, string[] types, IASTNode[] defaults, NestedEnv env, bool collect, out string err)
{
err = "";
int i = 0;
for (; i < ps.Length; i++)
{
if (i < args.Length)
{
if (types != null && i < types.Length && types[i] != null && types[i] != args[i].Type)
{
err += $"第{i}个参数，应为{types[i]}，却得到{args[i].Type}；";
}
else
{
env[ps[i]] = args[i];
}
}
else
{
env[ps[i]] = (defaults != null && i < defaults.Length) ? defaults[i].GetValue(null, env) : NilValue.Nil;
}
}
return(err.Length == 0);
}