您可以在ParseKit的令牌中使用通配符吗？

Question

I'm trying to add a symbol token using ParseKit below:

    [t.symbolState add:@"<p style=\"margin-left: 20px;\">"];

I'm wondering if ParseKit allows for wildcards when adding a symbol, such as:

    [t.symbolState add:@"<p style=\"margin-left: ##px;\">"];

I want to be able to then extract the wildcard from the token during the parsing procedure.

Is such a thing possible with ParseKit?

Answer 1

Developer of ParseKit here.

I think using ParseKit in this way is not a good idea.

ParseKit (and its successor PEGKit ) excel at tokenizing input and then parsing at the token level .

There are several natural tokens in the example input you've provided, but what you are trying to do here is ignore those natural tokens, combine them into a blob of input, and then do fancy sub-token matching using patterns.

There is a popular, powerful tool for fancy sub-token matching using patterns: Regular Expressions. They will be a much better solution for that kind of thing than PEGKit.

However, I still don't think Regular Expressions are the tool you want to use here (or, at least not the only tool).

It looks like you want to parse XML input. Don't use Regex or PEGKit for that. Use an XML parser. Always use an XML parser for parsing XML input.

You may choose to use another XML API layered on top of the XML Parser (SAX, StAX, DOM, XSLT, XQuery, etc.) but, underneath it all, you should be parsing with an XML parser (and, of course, all of those tools I listed, do).

See here for more info .

Then, once you have the style attribute string value you are looking for, use Regex to do fancy pattern matching.