Re: [PATCH v3 0/3] userdiff: Java updates

> On 2023-02-05T22:33 Johannes Sixt wrote:
>> Having seen all these examples, I think the following truncated
>> expression might do the right thing for all cases that are valid Java:
>>
>> "^[ \t]*(([a-z-]+[ \t]+)*(class|enum|interface|record)[ \t].*)$"
> 
> Only the '\n' is missing at the end, but otherwise I concur, so here's a v3.
> 
>> i.e., we recognize a whitespace in order to identify the keyword, and
>> then capture anything that follows without being specific. My reasoning
>> is that "class", "enum", "interface", and "record" cannot occur in any
>> other context than the beginning of a class definition. (But please do
>> correct me; I know next to nothing about Java syntax.)
> 
> The word "class" can also occur as part of a class literal, for example:
> 
>     Class<String> c = String.class;
> 
> but valid uses of class literals won't interfere with our regex, unless some
> wild formatting is applied.  This is technically valid Java:
> 
>     Class<String> c = String.
>     class 
>     ;
> 
> and with a space after lowercase "class", the v3 regex will trip.