enum nodetype {
	NODEIF, NODEELSE, NODEELSIF, NODEWHILE, NODEOP, NODENUM,
	NODEVAR,
};

struct parsenode {
	union {
		const char *var;
		char op;
	} val;
	const char *filename;
	struct parsenode *left, *right;
	int col, line, pos;
	enum nodetype type;
};

struct parsestate {
	struct tokenstate ts;
	struct parsenode *program;
	/* progsz is the total size of program */
	/* progind is the index (where to put the next tree) */
	size_t progsz, progind;
};

extern int parseall(struct parsestate *ps);