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#ifndef TREE_FRAGMENT
#define TREE_FRAGMENT
#include <iostream>
#include <vector>
#include <string>
#include "tdict.h"
namespace cdec {
static const unsigned NT_BIT = 0x40000000u;
static const unsigned FRONTIER_BIT = 0x80000000u;
static const unsigned ALL_MASK = 0x0FFFFFFFu;
inline bool IsInternalNT(unsigned x) {
return (x & NT_BIT);
}
inline bool IsFrontier(unsigned x) {
return (x & FRONTIER_BIT);
}
struct TreeFragmentProduction {
TreeFragmentProduction() {}
TreeFragmentProduction(int nttype, const std::vector<unsigned>& r) : lhs(nttype), rhs(r) {}
unsigned lhs;
std::vector<unsigned> rhs;
};
// this data structure represents a tree or forest
// productions can have mixtures of terminals and nonterminal symbols and non-terminal frontier sites
class TreeFragment {
public:
TreeFragment() : frontier_sites(), terminals() {}
// (S (NP a (X b) c d) (VP (V foo) (NP (NN bar))))
explicit TreeFragment(const std::string& tree, bool allow_frontier_sites = false);
void DebugRec(unsigned cur, std::ostream* out) const;
private:
// cp is the character index in the tree
// np keeps track of the nodes (nonterminals) that have been built
// symp keeps track of the terminal symbols that have been built
void ParseRec(const std::string& tree, bool afs, unsigned cp, unsigned symp, unsigned np, unsigned* pcp, unsigned* psymp, unsigned* pnp);
public:
unsigned root;
unsigned char frontier_sites;
unsigned short terminals;
std::vector<TreeFragmentProduction> nodes;
};
inline std::ostream& operator<<(std::ostream& os, const TreeFragment& x) {
x.DebugRec(x.nodes.size() - 1, &os);
return os;
}
}
#endif
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