bool Parser::EPrime()
{
bool plus = false;
if ("+" == lex) {
plus = true;
L.getTokLex(tok,lex);
} else if ("-" == lex) {
L.getTokLex(tok,lex);
} else {
// std::cout << "EPrime => null\n";
return true;
}
if (!Term()) return false;
if (plus) {
assembly.push_back(icode(a_line, "ADD"));
++a_line;
} else {
assembly.push_back(icode(a_line, "SUB"));
++a_line;
}
if (!EPrime()) return false;
// if (plus) {
// std::cout << "EPrime => + Term EPrime\n";
// } else {
// std::cout << "EPrime => - Term EPrime\n";
// }
return true;
}
bool Parser::TPrime()
{
bool div = false;
if ("*" == lex) {
L.getTokLex(tok,lex);
} else if ("/" == lex) {
div = true;
L.getTokLex(tok,lex);
} else {
// std::cout << "TPrime => null\n";
return true;
}
if (!Factor()) return false;
if (!TPrime()) return false;
if (div) {
assembly.push_back(icode(a_line, "DIV"));
++a_line;
} else {
assembly.push_back(icode(a_line, "MUL"));
++a_line;
}
// if (div) {
// std::cout << "TPrime => / Factor TPrime\n";
// } else {
// std::cout << "TPrime => * Factor TPrime\n";
// }
return true;
}
bool Parser::Factor()
{
if ("identifier" == tok) { //identifier or function call
// ident();
int a;
if (!get_symbol_addr(lex, a)) {
//++++++++++++++++++++++++++++++++++++++
// check funcs. if found call FuncCall(), else not declared
std::cout << "Error: Variable '" << lex << "' not declared.\n";
return false;
}
assembly.push_back(icode(a_line,"PUSHM",std::to_string(a)));
++a_line;
L.getTokLex(tok,lex);
// std::cout << "Factor => ident\n";
return true;
} else if ("integer" == tok) { //integer
assembly.push_back(icode(a_line,"PUSHV",lex));
++a_line;
// std::cout << "int = " << lex << std::endl;
L.getTokLex(tok,lex);
// std::cout << "Factor => int\n";
return true;
} else if ("real number" == tok) { // real
assembly.push_back(icode(a_line,"PUSHV",lex));
++a_line;
// std::cout << "real = " << lex << std::endl;
L.getTokLex(tok,lex);
// std::cout << "Factor => real\n";
return true;
} else if ("true" == lex) { //true
assembly.push_back(icode(a_line,"PUSHV","1"));
++a_line;
L.getTokLex(tok,lex);
// std::cout << "Factor => bool\n";
return true;
} else if ("false" == lex) { //false
assembly.push_back(icode(a_line,"PUSHV","0"));
++a_line;
L.getTokLex(tok,lex);
// std::cout << "Factor => bool\n";
return true;
} else if ("(" == lex) { // ( Expr )
L.getTokLex(tok,lex);
if (!Expr()) return false;
if (!(")" == lex)) {
std::cout << "Expression not closed by ')'\n";
return false;
} else {
L.getTokLex(tok,lex);
// std::cout << "Factor => ( Expr )\n";
return true;
}
} else {
std::cout << "Error parsing factor\n";
return false;
}
}
bool Parser::OptElseIf(int* jzp, std::vector< int > *jp)
{
if (!("elseif" == lex)) {
// std::cout << "OptElseIf => null\n";
return true;
} else {
L.getTokLex(tok,lex);
}
assembly.push_back(icode(a_line,"JUMP"));
(*jp).push_back(a_line-1);
++a_line;
assembly[(*jzp)].addr = std::to_string(a_line);
if (!("(" == lex)) {
std::cout << "elseif keyword not followed by '('\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!Condition()) return false;
if (!(")" == lex)) {
std::cout << "elseif condition not followed by ')'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!("begin" == lex)) {
std::cout << "elseif body does not begin with keyword 'begin'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
assembly.push_back(icode(a_line, "JMPZ"));
*jzp = a_line-1;
++a_line;
if (!OptStmtList()) return false;
if (!("end" == lex)) {
std::cout << "elseif body does not end with keyword 'end'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!OptElseIf(jzp, jp)) return false;
// std::cout << "OptElseIf => elseif ( Condition ) begin OptStmtList end OptElseIf\n";
return true;
}
bool Parser::While()
{
if (!("while" == lex)) {
std::cout << "Expected 'while'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!("(" == lex)) {
std::cout << "while keyword not followed by '('\n";
return false;
} else {
L.getTokLex(tok,lex);
}
int cond_line = a_line;
if (!Condition()) return false;
if (!(")" == lex)) {
std::cout << "while condition not followed by ')'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!("begin" == lex)) {
std::cout << "while body does not begin with keyword 'begin'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
assembly.push_back(icode(a_line, "JMPZ"));
int jz_instr = a_line-1;
++a_line;
if (!OptStmtList()) return false;
assembly.push_back(icode(a_line,"JUMP",std::to_string(cond_line)));
++a_line;
assembly[jz_instr].addr = std::to_string(a_line);
if (!("end" == lex)) {
std::cout << "while body does not end with keyword 'end'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
// std::cout << "While => while ( Condition ) begin OptStmtList end\n";
return true;
}
bool Parser::If()
{
// watch out for pointer magic in these 'if' 'elseif' 'else' functions
if (!("if" == lex)) {
std::cout << "Expected 'if'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!("(" == lex)) {
std::cout << "if keyword not followed by '('\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!Condition()) return false;
if (!(")" == lex)) {
std::cout << "if condition not followed by ')'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!("begin" == lex)) {
std::cout << "if body does not begin with keyword 'begin'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
assembly.push_back(icode(a_line, "JMPZ"));
int jz = a_line-1;
++a_line;
int *jzp = &(jz);
if (!OptStmtList()) return false;
if (!("end" == lex)) {
std::cout << "if body does not end with keyword 'end'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
std::vector< int > jumps;
std::vector< int > *jp = &jumps;
if (!OptElseIf(jzp, jp)) return false;
if (!OptElse(jz)) return false;
for (int i=0; i < jumps.size(); i++) {
assembly[jumps[i]].addr = std::to_string(a_line);
}
// std::cout << "If => if ( Condition ) begin OptStmtList end OptElseIf OptElse\n";
return true;
}
void Parser::end_nop()
{
for (int i = 0; i < assembly.size(); i++) {
if (assembly[i].instr == "JUMP" ||
assembly[i].instr == "JMPZ") {
if (std::to_string(a_line) == assembly[i].addr) {
assembly.push_back(icode(a_line, "NOP"));
return;
}
}
}
}
bool Parser::OptReads()
{
if (")" == lex) {
// std::cout << "OptVars => null\n";
return true;
}
if (!("," == lex)) {
std::cout << "Variable list not delimited by ','\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!("identifier" == tok)) {
std::cout << "Invalid identifier in variable list\n";
return false;
} else {
// ident();
int a;
if (!get_symbol_addr(lex, a)) {
std::cout << "Error: Variable '" << lex << "' not declared.\n";
return false;
}
assembly.push_back(icode(a_line,"PUSHI"));
++a_line;
assembly.push_back(icode(a_line,"POPM",std::to_string(a)));
++a_line;
L.getTokLex(tok,lex);
}
if (!OptReads()) return false;
// std::cout << "OptVars => , ident OptVars\n";
return true;
}
bool Parser::Condition()
{
if (!Expr()) return false;
if (!RelOp()) return false;
if (!Expr()) return false;
if (curr_relop == "<") {
assembly.push_back(icode(a_line, "LESS"));
++a_line;
} else if (curr_relop == ">") {
assembly.push_back(icode(a_line, "GRTR"));
++a_line;
} else if (curr_relop == "=") {
assembly.push_back(icode(a_line, "EQL"));
++a_line;
} else if (curr_relop == "<=") {
assembly.push_back(icode(a_line, "GRTR"));
++a_line;
assembly.push_back(icode(a_line, "NOT"));
++a_line;
} else if (curr_relop == ">=") {
assembly.push_back(icode(a_line, "LESS"));
++a_line;
assembly.push_back(icode(a_line, "NOT"));
++a_line;
} else if (curr_relop == "<>") {
assembly.push_back(icode(a_line, "EQL"));
++a_line;
assembly.push_back(icode(a_line, "NOT"));
++a_line;
} else {
std::cout << "Invalid relation encountered: " << curr_relop << std::endl;
return false;
}
// std::cout << "Condition => Expr RelOp Expr\n";
return true;
}
/*****************************************************************************************************************************
open
Prepares the database for use. An existing database is opened or otherwise an empty database is created.
If the database is openend a table _META with meta info is loaded into a dictionary _META. The dictionary key is the
code of the data element. A data element is either a tabel (dimension/event) or a field (characteristic/property).
The value of the dictionary is the MET_INFO structure. This structure contains meta data about the data element.
If the database is created an empty table _META is created.
The function calls virtual functions, db_, which must be overriden by a derived class for a specific database implementation.
******************************************************************************************************************************/
void ARAS::open(DBInfo dbInfo) {
if (isopen)
return;
// store db information
this->dbInfo = dbInfo;
// open or create database
// performs the database specific initialization code, the specific information to be used is stored in the struct DBInfo.
db_init_database();
// performs the database specific code to check whether a database alreay exists and open it.
if (db_open_database()) {
// read _META table from database into dictionary _META
TABLE values;
db_select_table("_META", {"CODE","INFO"}, values);
for (auto i : values)
_META.insert(std::pair<std::string, META_INFO>(i[0], META_INFO(i[1])));
}
else {
// performs the database specific code to create a new database based on DBInfo.
db_create_database();
// create table _META: define the columns
META_INFO imeta(data_type::DIM, 0, "_META", "", "", "_META", "CODE", 0, 0, 0, 0);
META_INFO icode(data_type::STR, SIZE_META_CODE_MAX, "_META", "", "","_META", "", 0, 0, 1, 0);
META_INFO idescs(data_type::STR, SIZE_DESCS_MAX, "_META", "", "", "_META", "", 0, 0, 0, 0);
META_INFO idescl(data_type::STR, SIZE_DESCL_MAX, "_META", "", "", "_META", "", 0, 0, 0, 0);
META_INFO iinfo(data_type::STR, 0, "_META", "", "", "_META", "",0, 0, 0, 0);
// define the table
META_TABLE meta = { { "_META", "Meta data", "Meta data", imeta }, { "CODE", "CODE", "CODE", icode }, { "DESCS", "Short Description", "Short Description", idescs }, { "DESCL", "Long Description", "Long Description", idescl }, { "INFO", "INFO", "INFO", iinfo } };
// performs the database specific code to create a new table
db_create_table(meta);
// load the meta data into the dictionary and the database table _META
for (auto i : meta)
insert_meta(i);
}
}
bool Parser::Write()
{
if (!("write" == lex)) {
std::cout << "Expected write\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!("(" == lex)) {
std::cout << "'write' keyword not followed by '('\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!Expr()) return false;
assembly.push_back(icode(a_line, "POPO"));
++a_line;
if (!(")" == lex)) {
std::cout << "Expression in Write not followed by ')'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
if (!(";" == lex)) {
std::cout << "Write statement not ended with ';'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
// std::cout << "Write => write ( Expr ) ;\n";
return true;
}
bool Parser::Assign()
{
int rhs;
if (!("identifier" == tok)) {
std::cout << "Expected identifier\n";
return false;
} else {
// ident();
if (!get_symbol_addr(lex, rhs)) {
std::cout << "Error: Variable '" << lex << "' not declared.\n";
return false;
}
L.getTokLex(tok,lex);
}
if (!("<-" == lex)) {
std::cout << "Expected assignment, missing '<-'\n" << lex;
return false;
} else {
L.getTokLex(tok,lex);
}
if (!Expr()) return false;
assembly.push_back(icode(a_line,"POPM",std::to_string(rhs)));
++a_line;
if (!(";" == lex)) {
std::cout << "Assignment not terminated by';'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
// std::cout << "Assign => ident <- Expr ;\n";
return true;
}
bool Parser::OptElse(int jz)
{
if (!("else" == lex)) {
// std::cout << "OptElse => null\n";
assembly[jz].addr = std::to_string(a_line);
return true;
} else {
L.getTokLex(tok,lex);
}
if (!("begin" == lex)) {
std::cout << "else body does not begin with keyword 'begin'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
assembly.push_back(icode(a_line, "JUMP"));
int jump_line = a_line-1;
++a_line;
assembly[jz].addr = std::to_string(a_line);
if (!OptStmtList()) return false;
if (!("end" == lex)) {
std::cout << "else body does not end with keyword 'end'\n";
return false;
} else {
L.getTokLex(tok,lex);
}
assembly[jump_line].addr = std::to_string(a_line);
// std::cout << "OptElse => else begin OptStmtList end\n";
return true;
}