- Added termMguSubTerm and termMguInTerm

This commit is contained in:
ccremers 2004-08-09 21:22:24 +00:00
parent a096aac6dd
commit 246c0c1c23
2 changed files with 73 additions and 0 deletions

View File

@ -159,3 +159,73 @@ termMguTerm (Term t1, Term t2)
}
return MGUFAIL;
}
//! Most general interm unifiers of t1 interm t2
/**
* Try to determine the most general interm unifiers of two terms.
*@returns Nothing. Iteration gets void.
*/
void
termMguInTerm (Term t1, Term t2, void (*iterator) ())
{
Termlist tl;
t2 = deVar (t2);
if (t2 != NULL && isTermTuple (t2))
{
// t2 is a tuple, consider interm options as well.
termMguInTerm (t1, t2->left.op1, iterator);
termMguInTerm (t1, t2->right.op2, iterator);
}
// simple clause or combined
tl = termMguTerm (t1, t2);
// Iterate
iterator ();
// Reset variables
termlistSubstReset (tl);
}
//! Most general subterm unifiers of t1 subterm t2
/**
* Try to determine the most general subterm unifiers of two terms.
*@returns Nothing. Iteration gets list of keys needed to decrypt.
*/
void
termMguSubTerm (Term t1, Term t2, void (*iterator) (),
const Termlist inverses, Termlist keylist)
{
Termlist tl;
t2 = deVar (t2);
if (t2 != NULL && !isTermLeaf (t2))
{
if (isTermTuple (t2))
{
// 'simple' tuple
termMguSubTerm (t1, t2->left.op1, iterator, inverses, keylist);
termMguSubTerm (t1, t2->right.op2, iterator, inverses, keylist);
}
else
{
// Must be encryption
// So, we need the key, and try to get the rest
Termlist keylist_new;
Term newkey;
keylist_new = termlistShallow (keylist);
newkey = inverseKey (inverses, t2->right.key);
keylist_new = termlistAdd (keylist_new, newkey);
// Recurse
termMguSubTerm (t1, t2->left.op, iterator, inverses, keylist_new);
termlistDelete (keylist_new);
termDelete (newkey);
}
}
// simple clause or combined
tl = termMguTerm (t1, t2);
// Iterate
iterator (keylist);
// Reset variables
termlistSubstReset (tl);
}

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@ -15,5 +15,8 @@
#define MGUFAIL (Termlist) -1
Termlist termMguTerm (Term t1, Term t2);
void termMguInTerm (Term t1, Term t2, void (*iterator) ());
void termMguSubTerm (Term t1, Term t2, void (*iterator) (),
const Termlist inverses, Termlist keylist);
#endif