#ifndef _X_STACK_H
#define _X_STACK_H


typedef struct x_stack* XStack;


XStack xstack_new(BitSet set);

void xstack_print(XStack stack, FILE* out);

int xstack_contains(XStack x, Symbol s);

int xstack_size(XStack x);

Symbol xstack_item(XStack x, int i);

void xstack_remove(XStack x, int i);

/** Returns an ArrayList of Symbols. First item is TOS */
ArrayList xstack_top(XStack x, int count);

void xstack_ensureReachable(XStack x, BitSet variables, int delve);

int compareVirtuals(Symbol s1, Symbol s2);

#endif