path: root/builtin.cpp

#include "builtin.h"
#include <cstdio>
#include <sstream>

using std::stringstream;

extern EmptyList *empty_list;

BoolObj::BoolObj(bool _val) : EvalObj(), val(_val) {}

bool BoolObj::is_true() { return val; }

string BoolObj::ext_repr() { return string(val ? "#t" : "#f"); }

#ifdef DEBUG
string BoolObj::_debug_repr() { return ext_repr(); }
#endif

IntObj::IntObj(int _val) : NumberObj(), val(_val) {}

string IntObj::ext_repr() {
    stringstream ss;
    ss << val;
    return ss.str();
}

#ifdef DEBUG
string IntObj::_debug_repr() { return ext_repr(); }
#endif

FloatObj::FloatObj(double _val) : NumberObj(), val(_val) {}

string FloatObj::ext_repr() { 
    stringstream ss;
    ss << val;
    return ss.str();
}

#ifdef DEBUG
string FloatObj::_debug_repr() { return ext_repr(); }
#endif

SpecialOptIf::SpecialOptIf() : SpecialOptObj() {}

void SpecialOptIf::prepare(Cons *pc) {
    state = 0;  // Prepared
    pc = pc->cdr;
    pc->skip = false;
    pc->cdr->skip = true;
    if (pc->cdr->cdr != empty_list)
        pc->cdr->cdr->skip = true;
}

void SpecialOptIf::pre_call(ArgList *args, Cons *pc,
        Environment *envt) {
    pc = dynamic_cast<Cons*>(pc->car); 
    // Condition evaluated and the decision is made
    state = 1;
    if (args->cdr->car->is_true())
    {
        pc = pc->cdr;
        pc->skip = true;
        pc->cdr->skip = false;
        if (pc->cdr->cdr != empty_list)
            pc->cdr->cdr->skip = true; // Eval the former
    }
    else
    {
        pc = pc->cdr;
        pc->skip = true;
        pc->cdr->skip = true;
        if (pc->cdr->cdr != empty_list)
            pc->cdr->cdr->skip = false; //Eval the latter
    }
}

EvalObj *SpecialOptIf::post_call(ArgList *args, Cons *pc,