Very slow parsing of certain grammars

[hansihe]

When running on certain grammars (Like this), parsing takes extremely long. Even simple rules like digit in the file linked takes over 20 seconds to finish.

Removing both the whitespace and comment rules does nothing to improve the runtime. Changing the size of the input doesn't seem to change much either Tests were done through the debugger.

This is probably me doing something stupid, and I appreciate any feedback you can provide.

[dragostis]

Seems odd that simple examples are running so slowly. There was a degenerate case that was slow a while ago, but it fixed on master, but that's definitely unrelate to why digit might be slow. I'll try to look into it soon. In the meantime, you could try to port this to pest 2.0 (master branch) and see if the same thing happens there. The differences between versions are quite small. Feel free to also reach for help on Gitter or build the 2.0 docs & book locally since they have been updated.