public override IDisposable BeginLookahead() {
BacktrackContext context = new BacktrackContext() { Location = CurrentLocation };
_bookmarks.Push(context);
return new DisposableAction(() => {
EndLookahead(context);
});
}
public override IDisposable BeginLookahead()
{
// Is this our first lookahead?
if (Buffer == null)
{
// Yes, setup the backtrack buffer
Buffer = new StringBuilder();
}
if (!Buffering)
{
// We're not already buffering, so we need to expand the buffer to hold the first character
ExpandBuffer();
Buffering = true;
}
// Mark the position to return to when we backtrack
// Use the closures and the "using" statement rather than an explicit stack
var context = new BacktrackContext()
{
BufferIndex = _currentBufferPosition,
Location = CurrentLocation
};
_backtrackStack.Push(context);
return(new DisposableAction(() =>
{
EndLookahead(context);
}));
}
private void EndLookahead(BacktrackContext context) {
if(_bookmarks.Count > 0 && Object.ReferenceEquals(_bookmarks.Peek(), context)) {
// Backtrack wasn't cancelled, so pop it
_bookmarks.Pop();
// Set the new current location
_tracker.CurrentLocation = context.Location;
InnerBuffer.Position = context.Location.AbsoluteIndex;
}
}
private void EndLookahead(BacktrackContext context)
{
// If the specified context is not the one on the stack, it was popped by a call to DoNotBacktrack
if (_backtrackStack.Count > 0 && ReferenceEquals(_backtrackStack.Peek(), context))
{
_backtrackStack.Pop();
_currentBufferPosition = context.BufferIndex;
_locationTracker.CurrentLocation = context.Location;
UpdateCurrentCharacter();
}
}
private void EndLookahead(BacktrackContext context)
{
if (_bookmarks.Count > 0 && ReferenceEquals(_bookmarks.Peek(), context))
{
// Backtrack wasn't cancelled, so pop it
_bookmarks.Pop();
// Set the new current location
_tracker.CurrentLocation = context.Location;
InnerBuffer.Position = context.Location.AbsoluteIndex;
}
}
public override IDisposable BeginLookahead()
{
BacktrackContext context = new BacktrackContext()
{
Location = CurrentLocation
};
_bookmarks.Push(context);
return(new DisposableAction(() => {
EndLookahead(context);
}));
}
public override IDisposable BeginLookahead() {
// Is this our first lookahead?
if (Buffer == null) {
// Yes, setup the backtrack buffer
Buffer = new StringBuilder();
}
if (!Buffering) {
// We're not already buffering, so we need to expand the buffer to hold the first character
ExpandBuffer();
Buffering = true;
}
// Mark the position to return to when we backtrack
// Use the closures and the "using" statement rather than an explicit stack
BacktrackContext context = new BacktrackContext() {
BufferIndex = _currentBufferPosition,
Location = CurrentLocation
};
_backtrackStack.Push(context);
return new DisposableAction(() => {
EndLookahead(context);
});
}
private void EndLookahead(BacktrackContext context)
{
// If the specified context is not the one on the stack, it was popped by a call to DoNotBacktrack
if (_backtrackStack.Count > 0 && ReferenceEquals(_backtrackStack.Peek(), context))
{
_backtrackStack.Pop();
_currentBufferPosition = context.BufferIndex;
_locationTracker.CurrentLocation = context.Location;
UpdateCurrentCharacter();
}
}