#ifndef SLP_H
#define SLP_H

#include "util.h"

typedef struct A_stm_ *A_stm;
typedef struct A_exp_ *A_exp;
typedef struct A_expList_ *A_expList;
typedef enum { A_plus, A_minus, A_times, A_div } A_binop;

struct A_stm_ {
	enum { A_compoundStm, A_assignStm, A_printStm } kind;
	union {
		struct {
			A_stm stm1, stm2;
		} compound;
		struct {
			string id;
			A_exp exp;
		} assign;
		struct {
			A_expList exps;
		} print;
	} u;
};
A_stm A_CompoundStm(A_stm stm1, A_stm stm2);
A_stm A_AssignStm(string id, A_exp exp);
A_stm A_PrintStm(A_expList exps);

struct A_exp_ {
	enum { A_idExp, A_numExp, A_opExp, A_eseqExp } kind;
	union {
		string id;
		int num;
		struct {
			A_exp left;
			A_binop oper;
			A_exp right;
		} op;
		struct {
			A_stm stm;
			A_exp exp;
		} eseq;
	} u;
};
A_exp A_IdExp(string id);
A_exp A_NumExp(int num);
A_exp A_OpExp(A_exp left, A_binop oper, A_exp right);
A_exp A_EseqExp(A_stm stm, A_exp exp);

struct A_expList_ {
	enum { A_pairExpList, A_lastExpList } kind;
	union {
		struct {
			A_exp head;
			A_expList tail;
		} pair;
		A_exp last;
	} u;
};

A_expList A_PairExpList(A_exp head, A_expList tail);
A_expList A_LastExpList(A_exp last);

#endif // SLP_H