Create Vale rule from working regex: How to conditionally match "Internet"

[daobrien]

I have the following PCRE2 regex (tested on regex101.com) which works correctly afaict:
(?<!\*\ )(?<!\n)Internet(?! Service Provider)(?! Protocol)

Use cases:

• "Internet" takes a lowercase "i" in most cases.
• Internet Protocol is an exception.
• Internet Service Provider is an exception.
• * Internet is an exception because that's how list items start in AsciiDoc.
• "Internet" at the beginning of a sentence is an exception.

I can't seem to get this working in Vale. Some example test strings:

I like the Internet contains an error.
Internet matches are good.

* Internet like this is ok.
* This Internet is not ok.

What is the internet.
The Internet Service Provider is ok.

The Internet Protocol is ok.

Thanks for any help.

[jdkato]

extends: existence
message: "'%s' should only be capitalized when starting a sentence."
level: error
nonword: true
scope:
  - heading
  - list
  - sentence
tokens:
  - (?<=\s)Internet(?! Service Provider| Protocol)

See also this Vale Studio session.

[daobrien]

Excellent, thanks! I was very close but my lookbehind was wrong. 👍

Does Vale have a specific flavor of regex that I should choose when testing in regex101.com? I do use Vale studio but I do a lot of testing in that web site as well.

Thanks again.
David

[jdkato]

There isn't a perfect match; Vale uses a superset of the Go flavor, supporting PCRE-style lookarounds.

The other thing to keep in mind is that, unless you're using scope: raw, you can't match against markup syntax (such as list indicators). The scoping system is generally a better solution here anyway, though.