/// <summary>
/// Given a Match, emits into the builder the evaluated
/// Right-to-Left substitution pattern.
/// </summary>
public void ReplacementImplRTL(ref SegmentStringBuilder segments, Match match)
{
for (int i = _rules.Length - 1; i >= 0; i--)
{
int rule = _rules[i];
ReadOnlyMemory <char> segment =
rule >= 0 ? _strings[rule].AsMemory() : // string lookup
rule < -Specials?match.GroupToStringImpl(-Specials - 1 - rule) : // group lookup
(-Specials - 1 - rule) switch // special insertion patterns
{
LeftPortion => match.GetLeftSubstring(),
RightPortion => match.GetRightSubstring(),
LastGroup => match.LastGroupToStringImpl(),
WholeString => match.Text.AsMemory(),
_ => default
};
// Add the segment to the list if it's not empty. A common case for it being
// empty is if the developer is using Regex.Replace as a way to implement
// Regex.Remove, where the replacement string is empty.
if (segment.Length != 0)
{
segments.Add(segment);
}
}
}
/// <summary>
/// Given a Match, emits into the builder the evaluated
/// Right-to-Left substitution pattern.
/// </summary>
public void ReplacementImplRTL(ref SegmentStringBuilder segments, Match match)
{
for (int i = _rules.Length - 1; i >= 0; i--)
{
int r = _rules[i];
if (r >= 0)
{
// string lookup
segments.Add(_strings[r].AsMemory());
}
else if (r < -Specials)
{
// group lookup
segments.Add(match.GroupToStringImpl(-Specials - 1 - r));
}
else
{
// special insertion patterns
switch (-Specials - 1 - r)
{
case LeftPortion:
segments.Add(match.GetLeftSubstring());
break;
case RightPortion:
segments.Add(match.GetRightSubstring());
break;
case LastGroup:
segments.Add(match.LastGroupToStringImpl());
break;
case WholeString:
segments.Add(match.Text.AsMemory());
break;
}
}
}
}