public static double callUser(UfnCall f)
{
Symbol fn = f.S; /* 函数名 */
SymList symList; /* 虚拟参数 */
AbstractAst args = f.L; /* 实际参数 */
double[] oldVal, newVal; /* 保存的参数值*/
double v;
int nargs;
if (fn.Func == null)
{
//yyerror("call to undefined function {}", fn.Name);
return(0);
}
/* 计算参数个数 */
symList = fn.SymbolList;
for (nargs = 0; symList != null; symList = symList.Next)
{
nargs++;
}
/* 为保存参数值做准备 */
oldVal = new double[nargs];
newVal = new double[nargs];
/* 计算参数值 */
for (int i = 0; i < nargs; i++)
{
if (args == null)
{
//yyerror("too few args in call to {}", fn.Name);
return(0.0);
}
if (args.NodeType == 'L') //是否是节点列表
{
newVal[i] = eval(((Ast)args).L);
args = ((Ast)args).R;
}
else //是否是列表末尾
{
newVal[i] = eval(args);
args = null;
}
}
/* 保存虚拟参数的旧值，赋予新值 */
symList = fn.SymbolList;
for (int i = 0; i < nargs; i++)
{
Symbol s = symList.Sym;
oldVal[i] = s.Value;
s.Value = newVal[i];
symList = symList.Next;
}
/* 计算函数 */
v = eval(fn.Func);
/* 恢复虚拟参数的值 */
return(v);
}
/// <summary>
/// 定义函数
/// </summary>
/// <param name="name"></param>
/// <param name=""></param>
public static void dodef(Symbol name, SymList syms, AbstractAst func)
{
name.SymbolList = syms;
name.Func = func;
}
