small python

#include <cstdio>#include <cstdlib>#include <cstring>#include <map>#include <string>#include <iostream>using namespace std;#define PyObject_Head\int ob_refcnt;\struct _typeobject * ob_type;#define PyObject_Head_Init(typePtr)\0, typePtr,// ----基本对象---------------------------------------typedef struct _object{PyObject_Head}PyObject;// ----类型对象---------------------------------------typedef PyObject* (*FunAdd)(PyObject*, PyObject*);typedef void (*FunPrint)(PyObject*);typedef long (*FunHash)(PyObject*);typedef struct _typeobject{PyObject_Headchar * name;FunAdd pyAdd;FunPrint pyPrint;FunHash pyHash;}PyTypeObject;PyTypeObject PyType_Tpye ={PyObject_Head_Init(&PyType_Tpye)"Type",0,0,0};// ----整数对象--------------------------------------typedef struct _intobject{PyObject_Headint val;}PyIntObject;PyObject* int_add(PyObject* left, PyObject* right);void int_print(PyObject * object);long int_hash(PyObject * object);PyTypeObject PyInt_Type ={PyObject_Head_Init(&PyType_Tpye)"int",int_add,int_print,int_hash,};PyObject* PyInt_Create(int val){PyIntObject * int_object = new PyIntObject;int_object->ob_refcnt = 1;int_object->ob_type = &PyInt_Type;int_object->val = val;return (PyObject*)int_object;}PyObject* int_add(PyObject* left, PyObject* right){PyIntObject * int_result = (PyIntObject*)PyInt_Create(0);PyIntObject * int_left = (PyIntObject*)left;PyIntObject * int_right = (PyIntObject*)right;int_result->val = int_left->val + int_right->val;return (PyObject*)int_result;}void int_print(PyObject * object){PyIntObject * int_object = (PyIntObject*)object;printf("%d\n", int_object->val);}long int_hash(PyObject * object){PyIntObject * int_object = (PyIntObject*)object;long x = int_object->val;if (x == -1)x = -2;return x;}//----字符串对象-----------------------------------------------typedef struct _strobject{PyObject_Headint length;long hash;char val[50];}PyStrObject;PyObject* str_add(PyObject* left, PyObject* right);void str_print(PyObject * object);long str_hash(PyObject * object);PyTypeObject PyStr_Type ={PyObject_Head_Init(&PyType_Tpye)"string",str_add,str_print,str_hash,};PyObject * PyStr_Create(const char * val){PyStrObject* str_object = new PyStrObject;str_object->ob_refcnt = 1;str_object->ob_type = &PyStr_Type;str_object->length = (val == NULL ? 0 : strlen(val));str_object->hash = -1;memset(str_object->val, 0, 50);if (val != NULL)strcpy(str_object->val, val);return (PyObject*)str_object;}PyObject * str_add(PyObject* left, PyObject* right){PyStrObject * str_result = (PyStrObject*)PyStr_Create(NULL);PyStrObject * str_left = (PyStrObject*)left;PyStrObject * str_right = (PyStrObject*)right;strcpy(str_result->val, str_left->val);strcat(str_result->val, str_right->val);return (PyObject*)str_result;}void str_print(PyObject* object){PyStrObject* str_object = (PyStrObject*)object;printf("%s\n", str_object->val);}long str_hash(PyObject * object){PyStrObject *str_object = (PyStrObject*)object;if (str_object->hash != -1){return str_object->hash;}int len;unsigned char * p;long x;len = str_object->length;p = (unsigned char *)str_object->val;x = *p << 7;while (--len >= 0){x = (1000003*x) ^ *p++;}x ^= str_object->length;if (x == -1)x = -2;str_object->hash = x;return x;}//----字典对象----------------------------------typedef struct _dictobject {PyObject_Headmap<long, PyObject*> dict;}PyDictObject;void dict_print(PyObject*);PyTypeObject PyDict_Type = {PyObject_Head_Init(&PyType_Tpye)"dict",0,dict_print,0};PyObject * PyDict_Create(){PyDictObject * dict_object = new PyDictObject;dict_object->ob_refcnt = 1;dict_object->ob_type = &PyDict_Type;return (PyObject*)dict_object;}void PyDict_SetItem(PyObject* target, PyObject* key, PyObject* val){PyDictObject* dict_object = (PyDictObject*)target;long hash_key = key->ob_type->pyHash(key);dict_object->dict[hash_key] = val;}PyObject* PyDict_GetItem(PyObject* target, PyObject* key){long hash_key = key->ob_type->pyHash(key);map<long, PyObject*>& dict = ((PyDictObject*)target)->dict;map<long, PyObject*>::iterator it = dict.find(hash_key);map<long, PyObject*>::iterator end = dict.end();if (it == end)return NULL;elsereturn it->second;}void dict_print(PyObject* object){PyDictObject * dict_object = (PyDictObject*)object;map<long, PyObject*>& dict = dict_object->dict;map<long, PyObject*>::iterator it = dict.begin();map<long, PyObject*>::iterator end = dict.end();printf("{\n");for ( ; it != end; ++it){printf("\t%ld : ", it->first);it->second->ob_type->pyPrint(it->second);}printf("}\n");}//----解释过程----------------------------------------------------PyObject* m_LocalEnv = PyDict_Create();PyObject* GetObjectBySymbol(string& symbol);void ExcutePrint(string& symbol);void ExcuteAdd(string& target, string& source);bool isSourceAllDigit(string& source);void ExcuteCommand(string& command){string::size_type pos;if ((pos = command.find("print ")) != string::npos){string tmp = command.substr(6);ExcutePrint(tmp);}else if ((pos = command.find(" = ")) != string::npos){string target = command.substr(0, pos);string source = command.substr(pos + 3);ExcuteAdd(target, source);}}PyObject* GetObjectBySymbol(string& symbol){PyObject* key = PyStr_Create(symbol.c_str());PyObject* val = PyDict_GetItem(m_LocalEnv, key);if (val == NULL){printf("[Error]: \"%s\" is not defined !\n", symbol.c_str());return NULL;}return val;}void ExcutePrint(string& symbol){PyObject* object = GetObjectBySymbol(symbol);if (object != NULL)object->ob_type->pyPrint(object);}void ExcuteAdd(string& target, string& source){if (target == "" || source == "")return;string::size_type pos;if (isSourceAllDigit(source)){PyObject* key = PyStr_Create(target.c_str());PyObject* val = PyInt_Create(atoi(source.c_str()));PyDict_SetItem(m_LocalEnv, key, val);}else if ((pos = source.find("\"")) != string::npos){PyObject* key = PyStr_Create(target.c_str());PyObject* val = PyStr_Create((source.substr(1, source.size()-2)).c_str());PyDict_SetItem(m_LocalEnv, key, val);}else if ((pos = source.find(" + ")) != string::npos){string left = source.substr(0, pos);string right = source.substr(pos + 3);PyObject* source_left = GetObjectBySymbol(left);PyObject* source_right = GetObjectBySymbol(right);if (source_left != NULL && source_right != NULL && source_left->ob_type == source_right->ob_type){PyObject* val = source_left->ob_type->pyAdd(source_left, source_right);PyObject* key = PyStr_Create(target.c_str());PyDict_SetItem(m_LocalEnv, key, val);}}//m_LocalEnv->ob_type->pyPrint(m_LocalEnv);}bool isSourceAllDigit(string& source){int len = source.size();for (int i=0; i<len; ++i)if (!isdigit(source[i]))return false;return true;}//----交互环境-----------------------------------------------string info = "      ****** Small Python ***********";string prompt = ">>> ";int main(){string m_Command;cout << info << endl;cout << prompt;while (getline(cin, m_Command)){if (m_Command == "");else if (m_Command == "exit")return 0;elseExcuteCommand(m_Command);cout << prompt;}}