struct D_t *parse_D(){
struct D_t *d = malloc(sizeof(struct D_t));
int m = nexttoken();
if(m == M_DEF){
eat_token();
d->kind = D_DEF;
m = nexttoken();
if(m == M_ID){
eat_token();
strcpy(d->str,yytext);
d->e = parse_E();
m = nexttoken();
if(m == M_SEMIC){
eat_token();
}else{
syntax_error();
}
}else{
syntax_error();
}
}else{
syntax_error();
}
return d;
}
void parse(char *e)
{
str = e;
i = 0;
parse_E();
if (str[i] == '\0')
return;
error("\'+\' or '\\0\'", str[i]);
return;
}
void parse_F()
{
char c = str[i];
if (isdigit(c)){
i++;
return;
}
if (c == '('){
i++;
parse_E();
c = str[i];
if (c == ')'){
i++;
return;
}
error("\')\'", c);
return;
}
error("\'0-9\' or \'(\'", c);
return;
}
struct E_t *parse_E(){
struct E_t *e = malloc(sizeof(struct E_t));
int m = nexttoken();
if(m == M_ID){
eat_token(); //IDは読み終わった
e->kind = E_ID;
strcpy(e->str,yytext);
}else if(m == M_NUM){ //NUMの場合
eat_token();
e->kind = E_NUM;
strcpy(e->str,yytext);
}else if(m == M_ADD){
eat_token();
e->kind = E_ADD;
e->e_left = parse_E();
e->e_right = parse_E();
}else if(m == M_SUB){
eat_token();
e->kind = E_SUB;
e->e_left = parse_E();
e->e_right = parse_E();
}else if(m == M_EQ){
eat_token();
e->kind = E_EQ;
e->e_left = parse_E();
e->e_right = parse_E();
}else if(m == M_LESS){
eat_token();
e->kind = E_LESS;
e->e_left = parse_E();
e->e_right = parse_E();
}else{
syntax_error();
}
return e;
}
struct C_t *parse_C(){
struct C_t *c = malloc(sizeof(struct C_t));
int m = nexttoken();
if(m == M_PRINT){
eat_token();
c->kind = C_PRINT;
c->e = parse_E();
m = nexttoken();
if(m == M_SEMIC){
eat_token();
}else{
syntax_error();
}
}else if(m == M_READ){
eat_token();
c->kind = C_READ;
m = nexttoken();
if(m == M_ID){
eat_token();
strcpy(c->str,yytext);
m = nexttoken();
if(m == M_SEMIC){
eat_token();
}else{
syntax_error();
}
}else{
syntax_error();
}
}else if(m == M_SET){
eat_token();
c->kind = C_SET;
m = nexttoken();
if(m == M_ID){
eat_token();
strcpy(c->str,yytext);
c->e = parse_E();
m = nexttoken();
if(m == M_SEMIC){
eat_token();
}else{
syntax_error();
}
}else{
syntax_error();
}
}else if(m == M_IF){
eat_token();
c->kind = C_IF;
c->e = parse_E();
m = nexttoken();
if(m == M_THEN){
eat_token();
c->b_left = parse_B();
m = nexttoken();
if(m == M_ELSE){
eat_token();
c->b_right = parse_B();
}else{
syntax_error();
}
}else{
syntax_error();
}
}else if(m == M_WHILE){
eat_token();
c->kind = C_WHILE;
c->e = parse_E();
m = nexttoken();
if(m == M_DO){
eat_token();
c->b = parse_B();
}else{
syntax_error();
}
}else{
syntax_error();
}
return c;
}