Re: Why I like functional programming

[dws]

One tiny nit in an otherwise great piece of code:  return show_err("Unended <$tag> detected"); I suspect that show_err() needs to escape HTML entities. Wrapping its arguments in <font> tags isn't sufficient.

[tilly]

That is one of several small mistakes in the code. Another is that there is only one allowed font attribute and it makes no sense. Another is that the RE engine has a bit of behaviour that I didn't understand when I wrote the code, and so I need to somewhere insert pos($raw) = pos($raw);. I leave verification that this is not a no-op, plus discovery of how this can lead to a bug, to a close reading of perlre. An important one pointed out by nate is that in reality the post will appear inside of a layout which is itself done with tables. Various tags that start new parts of a table should only be allowed inside of a table that you start. Plus he pointed out that some HTML tags take attributes which do not follow the usual pattern, for instance checkboxes can be "checked".

For these reasons and more, I did a rewrite at Functional take 2 which should have somewhat fewer bugs. I long ago made the decision that (partly because this site does not keep revision histories) I wanted to leave the original as it was, flaws and all.