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#include <cstdio>
#include "model.h"
#include "exc.h"
#include "consts.h"
FrameObj::FrameObj(ClassType _ftype) : ftype(_ftype) {}
EmptyList *empty_list = new EmptyList();
EmptyList::EmptyList() : Cons(NULL, NULL) {}
string EmptyList::ext_repr() { return string("()"); }
#ifdef DEBUG
string EmptyList::_debug_repr() { return ext_repr(); }
#endif
bool FrameObj::is_ret_addr() {
return ftype & CLS_RET_ADDR;
}
EvalObj::EvalObj(ClassType _otype) : FrameObj(CLS_EVAL_OBJ), otype(_otype) {}
void EvalObj::prepare(Cons *pc) {}
bool EvalObj::is_simple_obj() {
return otype & CLS_SIM_OBJ;
}
bool EvalObj::is_sym_obj() {
return otype & CLS_SYM_OBJ;
}
bool EvalObj::is_opt_obj() {
return otype & CLS_OPT_OBJ;
}
#ifdef DEBUG
void EvalObj::_debug_print() {
printf("mem: 0x%llX\n%s\n\n", (unsigned long long)this,
_debug_repr().c_str());
}
#endif
bool EvalObj::is_true() {
return true;
}
Cons::Cons(EvalObj *_car, Cons *_cdr) :
EvalObj(CLS_CONS_OBJ), car(_car), cdr(_cdr), skip(false),
next(cdr == empty_list ? NULL : cdr) {}
string Cons::ext_repr() { return string("#<Cons>"); }
#ifdef DEBUG
string Cons::_debug_repr() { return ext_repr(); }
void Cons::_debug_print() {
printf("mem: 0x%llX (0x%llX . 0x%llX) | 0x%llX\n%s\n",
(unsigned long long)this,
(unsigned long long)car,
(unsigned long long)cdr,
(unsigned long long)next,
("car: " + car -> ext_repr() + "\n" + \
"cdr: " + cdr -> ext_repr() + "\n").c_str());
}
#endif
RetAddr::RetAddr(Cons *_addr) : FrameObj(CLS_RET_ADDR), addr(_addr) {}
#ifdef DEBUG
string RetAddr::_debug_repr() { return string("#<Return Address>"); }
#endif
UnspecObj::UnspecObj() : EvalObj() {}
string UnspecObj::ext_repr() { return string("#<Unspecified>"); }
#ifdef DEBUG
string UnspecObj::_debug_repr() { return ext_repr(); }
#endif
SymObj::SymObj(const string &str) :
EvalObj(CLS_SIM_OBJ | CLS_SYM_OBJ), val(str) {}
string SymObj::ext_repr() { return "#<Symbol: " + val + ">"; }
#ifdef DEBUG
string SymObj::_debug_repr() { return ext_repr(); }
#endif
OptObj::OptObj() : EvalObj(CLS_SIM_OBJ | CLS_OPT_OBJ) {}
ProcObj::ProcObj(ASTList *_body,
Environment *_envt,
SymbolList *_para_list) :
OptObj(), body(_body), envt(_envt), para_list(_para_list) {}
Cons *ProcObj::call(ArgList *args, Environment * &genvt,
Continuation * &cont, FrameObj ** &top_ptr) {
// Create a new continuation
// static_cast see `call` invocation in eval.cpp
Cons *ret_addr = static_cast<RetAddr*>(*top_ptr)->addr;
Continuation *_cont = new Continuation(genvt, ret_addr, cont, body);
// Create local env and recall the closure
Environment *_envt = new Environment(envt);
// static_cast<SymObj*> because the para_list is already checked
Cons *ptr, *ppar;
for (ptr = args->cdr, ppar = para_list;
ptr != empty_list && ppar != empty_list;
ptr = ptr->cdr, ppar = ppar->cdr)
_envt->add_binding(static_cast<SymObj*>(ppar->car), ptr->car);
if (ptr != empty_list || ppar != empty_list)
throw TokenError("", RUN_ERR_WRONG_NUM_OF_ARGS);
genvt = _envt;
cont = _cont;
*top_ptr++ = new RetAddr(NULL); // Mark the entrance of a cont
return body; // Move pc to the proc entry point
}
string ProcObj::ext_repr() { return string("#<Procedure>"); }
#ifdef DEBUG
string ProcObj::_debug_repr() { return ext_repr(); }
#endif
SpecialOptObj::SpecialOptObj() : OptObj() {}
NumberObj::NumberObj() : EvalObj() {}
BuiltinProcObj::BuiltinProcObj(BuiltinProc f, string _name) :
OptObj(), handler(f), name(_name) {}
Cons *BuiltinProcObj::call(ArgList *args, Environment * &envt,
Continuation * &cont, FrameObj ** &top_ptr) {
Cons *ret_addr = static_cast<RetAddr*>(*top_ptr)->addr;
*top_ptr++ = handler(args->cdr);
return ret_addr->next; // Move to the next instruction
}
string BuiltinProcObj::ext_repr() {
return "#<Builtin Procedure: " + name + ">";
}
#ifdef DEBUG
string BuiltinProcObj::_debug_repr() { return ext_repr(); }
#endif
Environment::Environment(Environment *_prev_envt) : prev_envt(_prev_envt) {}
bool Environment::add_binding(SymObj *sym_obj, EvalObj *eval_obj, bool def) {
bool has_key = binding.count(sym_obj->val);
if (!def && !has_key) return false;
binding[sym_obj->val] = eval_obj;
return true;
}
EvalObj *Environment::get_obj(EvalObj *obj) {
if (!obj->is_sym_obj()) return obj;
SymObj *sym_obj = static_cast<SymObj*>(obj);
string name(sym_obj->val);
for (Environment *ptr = this; ptr; ptr = ptr->prev_envt)
{
bool has_key = ptr->binding.count(name);
if (has_key) return ptr->binding[name];
}
// Object not found
throw TokenError(name, RUN_ERR_UNBOUND_VAR);
}
Continuation::Continuation(Environment *_envt, Cons *_pc,
Continuation *_prev_cont,
ASTList *_proc_body) :
envt(_envt), pc(_pc), prev_cont(_prev_cont),
proc_body(_proc_body) {}
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