private void HandleExplicitNumericGroups(ArrayList explicit_numeric_groups)
{
int gid = gap;
int i = 0;
int n_explicit = explicit_numeric_groups.Count;
explicit_numeric_groups.Sort();
// move 'gap' forward to skip over all explicit groups that
// turn out to match their index
for (; i < n_explicit; ++i)
{
CapturingGroup g = (CapturingGroup)explicit_numeric_groups [i];
if (g.Index > gid)
{
break;
}
if (g.Index == gid)
{
gid++;
}
}
gap = gid;
// re-index all further groups so that the indexes are contiguous
int prev = gid;
for (; i < n_explicit; ++i)
{
CapturingGroup g = (CapturingGroup)explicit_numeric_groups [i];
if (g.Index == prev)
{
g.Index = gid - 1;
}
else
{
prev = g.Index;
g.Index = gid++;
}
}
}
public int GetMapping(Hashtable mapping)
{
int end = caps.Count;
mapping.Add("0", 0);
for (int i = 0; i < end; i++)
{
CapturingGroup group = (CapturingGroup)caps [i];
string name = group.Name != null ? group.Name : group.Index.ToString();
if (mapping.Contains(name))
{
if ((int)mapping [name] != group.Index)
{
throw new SystemException("invalid state");
}
continue;
}
mapping.Add(name, group.Index);
}
return(gap);
}
private Expression ParseGroupingConstruct(ref RegexOptions options)
{
if (pattern[ptr] != '?')
{
Group group;
if (IsExplicitCapture(options))
{
group = new Group();
}
else
{
group = new CapturingGroup();
caps.Add(group);
}
ParseGroup(group, options, null);
return(group);
}
else
{
++ptr;
}
switch (pattern[ptr])
{
case ':': { // non-capturing group
++ptr;
Group group = new Group();
ParseGroup(group, options, null);
return(group);
}
case '>': { // non-backtracking group
++ptr;
Group group = new NonBacktrackingGroup();
ParseGroup(group, options, null);
return(group);
}
case 'i':
case 'm':
case 'n':
case 's':
case 'x':
case '-': { // options
RegexOptions o = options;
ParseOptions(ref o, false);
if (pattern[ptr] == '-')
{
++ptr;
ParseOptions(ref o, true);
}
if (pattern[ptr] == ':') // pass options to child group
{
++ptr;
Group group = new Group();
ParseGroup(group, o, null);
return(group);
}
else if (pattern[ptr] == ')') // change options of enclosing group
{
++ptr;
options = o;
return(null);
}
else
{
throw NewParseException("Bad options");
}
}
case '<':
case '=':
case '!': { // lookahead/lookbehind
ExpressionAssertion asn = new ExpressionAssertion();
if (!ParseAssertionType(asn))
{
goto case '\''; // it's a (?<name> ) construct
}
Group test = new Group();
ParseGroup(test, options, null);
asn.TestExpression = test;
return(asn);
}
case '\'': { // named/balancing group
char delim;
if (pattern[ptr] == '<')
{
delim = '>';
}
else
{
delim = '\'';
}
++ptr;
string name = ParseName();
if (pattern[ptr] == delim)
{
// capturing group
if (name == null)
{
throw NewParseException("Bad group name.");
}
++ptr;
CapturingGroup cap = new CapturingGroup();
cap.Name = name;
caps.Add(cap);
ParseGroup(cap, options, null);
return(cap);
}
else if (pattern[ptr] == '-')
{
// balancing group
++ptr;
string balance_name = ParseName();
if (balance_name == null || pattern[ptr] != delim)
{
throw NewParseException("Bad balancing group name.");
}
++ptr;
BalancingGroup bal = new BalancingGroup();
bal.Name = name;
if (bal.IsNamed)
{
caps.Add(bal);
}
refs.Add(bal, balance_name);
ParseGroup(bal, options, null);
return(bal);
}
else
{
throw NewParseException("Bad group name.");
}
}
case '(': { // expression/capture test
Assertion asn;
++ptr;
int p = ptr;
string name = ParseName();
if (name == null || pattern[ptr] != ')') // expression test
// FIXME MS implementation doesn't seem to
// implement this version of (?(x) ...)
{
ptr = p;
ExpressionAssertion expr_asn = new ExpressionAssertion();
if (pattern[ptr] == '?')
{
++ptr;
if (!ParseAssertionType(expr_asn))
{
throw NewParseException("Bad conditional.");
}
}
else
{
expr_asn.Negate = false;
expr_asn.Reverse = false;
}
Group test = new Group();
ParseGroup(test, options, null);
expr_asn.TestExpression = test;
asn = expr_asn;
}
else // capture test
{
++ptr;
asn = new CaptureAssertion(new Literal(name, IsIgnoreCase(options)));
refs.Add(asn, name);
}
Group group = new Group();
ParseGroup(group, options, asn);
return(group);
}
case '#': { // comment
++ptr;
while (pattern[ptr++] != ')')
{
if (ptr >= pattern.Length)
{
throw NewParseException("Unterminated (?#...) comment.");
}
}
return(null);
}
default: // error
throw NewParseException("Bad grouping construct.");
}
}
private void ResolveReferences()
{
int gid = 1;
Hashtable dict = new Hashtable();
ArrayList explicit_numeric_groups = null;
// number unnamed groups
foreach (CapturingGroup group in caps)
{
if (group.Name != null)
{
continue;
}
dict.Add(gid.ToString(), group);
group.Index = gid++;
++num_groups;
}
// number named groups
foreach (CapturingGroup group in caps)
{
if (group.Name == null)
{
continue;
}
if (dict.Contains(group.Name))
{
CapturingGroup prev = (CapturingGroup)dict [group.Name];
group.Index = prev.Index;
if (group.Index == gid)
{
gid++;
}
else if (group.Index > gid)
{
explicit_numeric_groups.Add(group);
}
continue;
}
if (Char.IsDigit(group.Name [0]))
{
int ptr = 0;
int group_gid = ParseDecimal(group.Name, ref ptr);
if (ptr == group.Name.Length)
{
group.Index = group_gid;
dict.Add(group.Name, group);
++num_groups;
if (group_gid == gid)
{
gid++;
}
else
{
// all numbers before 'gid' are already in the dictionary. So, we know group_gid > gid
if (explicit_numeric_groups == null)
{
explicit_numeric_groups = new ArrayList(4);
}
explicit_numeric_groups.Add(group);
}
continue;
}
}
string gid_s = gid.ToString();
while (dict.Contains(gid_s))
{
gid_s = (++gid).ToString();
}
dict.Add(gid_s, group);
dict.Add(group.Name, group);
group.Index = gid++;
++num_groups;
}
gap = gid; // == 1 + num_groups, if explicit_numeric_groups == null
if (explicit_numeric_groups != null)
{
HandleExplicitNumericGroups(explicit_numeric_groups);
}
// resolve references
foreach (Expression expr in refs.Keys)
{
string name = (string)refs [expr];
if (!dict.Contains(name))
{
if (expr is CaptureAssertion && !Char.IsDigit(name [0]))
{
continue;
}
BackslashNumber bn = expr as BackslashNumber;
if (bn != null && bn.ResolveReference(name, dict))
{
continue;
}
throw NewParseException("Reference to undefined group " +
(Char.IsDigit(name[0]) ? "number " : "name ") +
name);
}
CapturingGroup group = (CapturingGroup)dict[name];
if (expr is Reference)
{
((Reference)expr).CapturingGroup = group;
}
else if (expr is CaptureAssertion)
{
((CaptureAssertion)expr).CapturingGroup = group;
}
else if (expr is BalancingGroup)
{
((BalancingGroup)expr).Balance = group;
}
}
}
