std::set<Crag::CragEdge>
Crag::leafEdges(CragNode n) const {
std::set<CragNode> nleafNodes = leafNodes(n);
std::set<CragEdge> leafEdges;
for (CragNode u : nleafNodes)
for (CragNode v : nleafNodes) {
if (id(u) >= id(v))
continue;
for (CragEdge e : adjEdges(u))
if (isLeafEdge(e))
if (nleafNodes.count(oppositeNode(u, e)))
leafEdges.insert(e);
}
return leafEdges;
}
//-----------------------------------------------------------------------------
//
// calcChainedFollowPos. Modify the previously calculated followPos sets
// to implement rule chaining. NOT described by Aho
//
//-----------------------------------------------------------------------------
void RBBITableBuilder::calcChainedFollowPos(RBBINode *tree) {
UVector endMarkerNodes(*fStatus);
UVector leafNodes(*fStatus);
int32_t i;
if (U_FAILURE(*fStatus)) {
return;
}
// get a list of all endmarker nodes.
tree->findNodes(&endMarkerNodes, RBBINode::endMark, *fStatus);
// get a list all leaf nodes
tree->findNodes(&leafNodes, RBBINode::leafChar, *fStatus);
if (U_FAILURE(*fStatus)) {
return;
}
// Get all nodes that can be the start a match, which is FirstPosition()
// of the portion of the tree corresponding to user-written rules.
// See the tree description in bofFixup().
RBBINode *userRuleRoot = tree;
if (fRB->fSetBuilder->sawBOF()) {
userRuleRoot = tree->fLeftChild->fRightChild;
}
U_ASSERT(userRuleRoot != NULL);
UVector *matchStartNodes = userRuleRoot->fFirstPosSet;
// Iteratate over all leaf nodes,
//
int32_t endNodeIx;
int32_t startNodeIx;
for (endNodeIx=0; endNodeIx<leafNodes.size(); endNodeIx++) {
RBBINode *tNode = (RBBINode *)leafNodes.elementAt(endNodeIx);
RBBINode *endNode = NULL;
// Identify leaf nodes that correspond to overall rule match positions.
// These include an endMarkerNode in their followPos sets.
for (i=0; i<endMarkerNodes.size(); i++) {
if (tNode->fFollowPos->contains(endMarkerNodes.elementAt(i))) {
endNode = tNode;
break;
}
}
if (endNode == NULL) {
// node wasn't an end node. Try again with the next.
continue;
}
// We've got a node that can end a match.
// Line Break Specific hack: If this node's val correspond to the $CM char class,
// don't chain from it.
// TODO: Add rule syntax for this behavior, get specifics out of here and
// into the rule file.
if (fRB->fLBCMNoChain) {
UChar32 c = this->fRB->fSetBuilder->getFirstChar(endNode->fVal);
if (c != -1) {
// c == -1 occurs with sets containing only the {eof} marker string.
ULineBreak cLBProp = (ULineBreak)u_getIntPropertyValue(c, UCHAR_LINE_BREAK);
if (cLBProp == U_LB_COMBINING_MARK) {
continue;
}
}
}
// Now iterate over the nodes that can start a match, looking for ones
// with the same char class as our ending node.
RBBINode *startNode;
for (startNodeIx = 0; startNodeIx<matchStartNodes->size(); startNodeIx++) {
startNode = (RBBINode *)matchStartNodes->elementAt(startNodeIx);
if (startNode->fType != RBBINode::leafChar) {
continue;
}
if (endNode->fVal == startNode->fVal) {
// The end val (character class) of one possible match is the
// same as the start of another.
// Add all nodes from the followPos of the start node to the
// followPos set of the end node, which will have the effect of
// letting matches transition from a match state at endNode
// to the second char of a match starting with startNode.
setAdd(endNode->fFollowPos, startNode->fFollowPos);
}
}
}
}
