#ifndef STFUNC_H
#define STFUNC_H

#include <string>
#include "value.h"
#include "nt.h"

using std::string;

// Interface function to standard functions in Delta
typedef void (*StdFunc)(
    int numArgs,            // actual number of arguments
    const ValuePtr* args,   // array of pointers to arguments
    Value* res              // resulting value
);

const int STDFUNC_RES_LVALUE = 1; // First arg and result are the same!

class StdFuncDef {
public:
    string name;        // function name
    int numArgs;        // (-1) for indefinite number of arguments
    StdFunc func;       // Interface function
    int modifiers;

    StdFuncDef():
        name(),
        numArgs(0),
        func(0),
        modifiers(0)
    {}

    StdFuncDef(const string& n, int nArgs, StdFunc f, int m = 0):
        name(n),
        numArgs(nArgs),
        func(f),
        modifiers(m)
    {}

    bool resIsLValue() const {
        return ((modifiers & STDFUNC_RES_LVALUE) != 0);
    }
};

// Globals
const StdFuncDef* findStandardFunction(const string& name);
void addStandardFunctionsToNameTable(NameTable& nt);

typedef const StdFuncDef* StdFuncDefPtr;

#endif