private static RTree ParseValueReference(RevgexStringReader inp, GroupSet groups)
{
inp.Read(); // '$'
var c = inp.Peek();
if (c >= '0' && c <= '9')
{
var groupId = inp.Read() - '0';
c = inp.Peek();
if (c >= '0' && c <= '9')
{
groupId = groupId * 10 + (inp.Read() - '0');
}
if (groupId == 0)
{
throw Error(inp, "Value backreference to the entire patternt (zero-th group) is not allowed.");
}
if (groups.Get(groupId) == null)
{
throw Error(inp, "Invalid group backreference.");
}
return(new RGroupValueRef(groupId, LookupQuantifier(inp)));
}
switch (c)
{
case -1:
throw Error(inp, "Incomplete group value backreference.");
case ':':
var groupName = ParseGroupName(inp);
if (groups.Get(groupName) == null)
{
throw Error(inp, "Invalid named group value backreference.");
}
return(new RNamedGroupValueRef(groupName, LookupQuantifier(inp)));
case '(':
inp.Read();
var groupId = 0;
c = inp.Peek();
do
{
if (c < '0' || c > '9')
{
throw Error(inp, "Invalid group value backreference.");
}
groupId = groupId * 10 + (inp.Read() - '0');
} while ((c = inp.Peek()) != ')');
inp.Read(); // ')'
if (groups.Get(groupId) == null)
{
throw Error(inp, "Invalid group value backreference.");
}
return(new RGroupValueRef(groupId, LookupQuantifier(inp)));
default: throw Error(inp, "Invalid group value backreference.");
}
}
public Revgex(string str, bool ignoreLineEndings = false, bool ignoreWhitespace = false, bool allowPredefinedGroups = true)
{
groups = str.Length == 0
? new GroupSet()
: Parser.Parse(str.Replace("\r\n", "\n").Replace('\r', '\n'), ignoreLineEndings, ignoreWhitespace, allowPredefinedGroups);
tree = groups.Get(0) ?? REmpty.Instance;
}
private static RTree ParseEscapeSequence(RevgexStringReader inp, GroupSet groups)
{
inp.Read(); // '\'
var c = inp.Peek();
if (c >= '0' && c <= '9')
{
var groupId = inp.Read() - '0';
c = inp.Peek();
if (c >= '0' && c <= '9')
{
groupId = groupId * 10 + (inp.Read() - '0');
}
if (groupId == 0)
{
throw Error(inp, "Backreference to the entire patternt (zero-th group) is not allowed.");
}
if (groups.Get(groupId) == null)
{
throw Error(inp, "Invalid group backreference.");
}
return(new RGroupRef(groupId, LookupQuantifier(inp)));
}
switch (c)
{
case -1:
throw Error(inp, "Incomplete escape sequence.");
case ':':
var groupName = ParseGroupName(inp);
if (groups.Get(groupName) == null)
{
throw Error(inp, "Invalid named group backreference.");
}
return(new RNamedGroupRef(groupName, LookupQuantifier(inp)));
case '(':
inp.Read();
var groupId = 0;
c = inp.Peek();
do
{
if (c < '0' || c > '9')
{
throw Error(inp, "Invalid group backreference.");
}
groupId = groupId * 10 + (inp.Read() - '0');
} while ((c = inp.Peek()) != ')');
inp.Read(); // ')'
if (groups.Get(groupId) == null)
{
throw Error(inp, "Invalid group backreference.");
}
return(new RGroupRef(groupId, LookupQuantifier(inp)));
case 'w':
inp.Read();
return(RChar.w(LookupQuantifier(inp)));
case 'W':
inp.Read();
return(RChar.W(LookupQuantifier(inp)));
case 's':
inp.Read();
return(RChar.s(LookupQuantifier(inp)));
case 'S':
inp.Read();
return(RChar.S(LookupQuantifier(inp)));
case 'd':
inp.Read();
return(RChar.d(LookupQuantifier(inp)));
case 'D':
inp.Read();
return(RChar.D(LookupQuantifier(inp)));
default:
return(new RFixedString(inp.Read().ToString(), LookupQuantifier(inp)));
}
}
