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- Lots of stuff starts to take shape. Nice.

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This commit is contained in:
ccremers
2004-08-11 14:09:12 +00:00
parent f30207b059
commit 2191d80885
5 changed files with 223 additions and 40 deletions
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39
src/mgu.c
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@@ -163,49 +163,59 @@ termMguTerm (Term t1, Term t2)
//! Most general interm unifiers of t1 interm t2
/**
* Try to determine the most general interm unifiers of two terms.
*@returns Nothing. Iteration gets void.
*@returns Nothing. Iteration gets termlist of substitutions.
*/
void
termMguInTerm (Term t1, Term t2, void (*iterator) ())
int
termMguInTerm (Term t1, Term t2, int (*iterator) ())
{
Termlist tl;
int flag;
flag = 1;
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);
flag = flag & termMguInTerm (t1, t2->left.op1, iterator);
flag = flag & termMguInTerm (t1, t2->right.op2, iterator);
}
// simple clause or combined
tl = termMguTerm (t1, t2);
if (tl != MGUFAIL)
{
// Iterate
iterator ();
flag = flag & iterator (tl);
// Reset variables
termlistSubstReset (tl);
}
return flag;
}
//! 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.
*@returns Nothing. Iteration gets termlist of subst, and list of keys needed to decrypt.
*/
void
termMguSubTerm (Term t1, Term t2, void (*iterator) (),
int
termMguSubTerm (Term t1, Term t2, int (*iterator) (),
const Termlist inverses, Termlist keylist)
{
int flag;
Termlist tl;
flag = 1;
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);
flag =
flag & termMguSubTerm (t1, t2->left.op1, iterator, inverses,
keylist);
flag =
flag & termMguSubTerm (t1, t2->right.op2, iterator, inverses,
keylist);
}
else
{
@@ -219,7 +229,9 @@ termMguSubTerm (Term t1, Term t2, void (*iterator) (),
keylist_new = termlistAdd (keylist_new, newkey);
// Recurse
termMguSubTerm (t1, t2->left.op, iterator, inverses, keylist_new);
flag =
flag & termMguSubTerm (t1, t2->left.op, iterator, inverses,
keylist_new);
termlistDelete (keylist_new);
termDelete (newkey);
@@ -230,8 +242,9 @@ termMguSubTerm (Term t1, Term t2, void (*iterator) (),
if (tl != MGUFAIL)
{
// Iterate
iterator (keylist);
flag = flag & iterator (tl, keylist);
// Reset variables
termlistSubstReset (tl);
}
return flag;
}