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static private FirstChars ( |
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| t | ||
| return | ||
/// <summary>
/// The top level RegexCode generator. It does a depth-first walk
/// through the tree and calls EmitFragment to emits code before
/// and after each child of an interior node, and at each leaf.
///
/// It runs two passes, first to count the size of the generated
/// code, and second to generate the code.
///
/// We should time it against the alternative, which is
/// to just generate the code and grow the array as we go.
/// </summary>
private RegexCode RegexCodeFromRegexTree(RegexTree tree)
{
RegexNode curNode;
int curChild;
int capsize;
RegexPrefix fcPrefix;
RegexPrefix prefix;
int anchors;
RegexBoyerMoore bmPrefix;
bool rtl;
// construct sparse capnum mapping if some numbers are unused
if (tree._capnumlist == null || tree._captop == tree._capnumlist.Length)
{
capsize = tree._captop;
_caps = null;
}
else
{
capsize = tree._capnumlist.Length;
_caps = tree._caps;
for (int i = 0; i < tree._capnumlist.Length; i++)
{
_caps[tree._capnumlist[i]] = i;
}
}
_capPositions = new int[capsize];
_counting = true;
for (; ;)
{
if (!_counting)
{
_emitted = new int[_count];
}
curNode = tree._root;
curChild = 0;
Emit(RegexCode.Lazybranch, 0);
for (; ;)
{
if (curNode._children == null)
{
EmitFragment(curNode._type, curNode, 0);
}
else if (curChild < curNode._children.Count)
{
EmitFragment(curNode._type | BeforeChild, curNode, curChild);
curNode = curNode._children[curChild];
PushInt(curChild);
curChild = 0;
continue;
}
if (EmptyStack())
{
break;
}
curChild = PopInt();
curNode = curNode._next;
EmitFragment(curNode._type | AfterChild, curNode, curChild);
curChild++;
}
PatchJump(0, CurPos());
Emit(RegexCode.Stop);
if (!_counting)
{
break;
}
_counting = false;
}
fcPrefix = RegexFCD.FirstChars(tree);
prefix = RegexFCD.Prefix(tree);
rtl = ((tree._options & RegexOptions.RightToLeft) != 0);
CultureInfo culture = (tree._options & RegexOptions.CultureInvariant) != 0 ? CultureInfo.InvariantCulture : CultureInfo.CurrentCulture;
if (prefix != null && prefix.Prefix.Length > 0)
{
bmPrefix = new RegexBoyerMoore(prefix.Prefix, prefix.CaseInsensitive, rtl, culture);
}
else
{
bmPrefix = null;
}
anchors = RegexFCD.Anchors(tree);
return(new RegexCode(_emitted, _stringtable, _trackcount, _caps, capsize, bmPrefix, fcPrefix, anchors, rtl, _resetMatchStartFound, _capPositions));
}
