[ruby-core:17755] Re: [PATCH] ruby-mode.el: Fix here-doc strings with inner quotes

Here's a third patch that fixes a bug in the second and uses a quicker 
method of determining if the point is in a here-doc. To do so, it 
enables parse-sexp-lookup-properties, which causes syntax-sensitive 
functions to respect font-lock-syntactic-keywords. I think this is a 
good thing to enable in general, because it means that forward-sexp and 
similar functions treat regexps the same way they treat strings and so 
forth.

Nathan Weizenbaum wrote:
> It was designed to fix the following case:
>
> <<FOO
> "
> FOO
> bar
>
> where "bar" is wrongly highlighted in font-lock-string-face. It also 
> fixes the following case:
>
> <<FOO
> <<BAR
> BAR
> FOO
>
> in which FOO is *not* highlighted in font-lock-string-face when it 
> should be.
>
> I've attached a modified version that works with the case you pointed 
> out.
>
> Yukihiro Matsumoto wrote:
>> In message "Re: [ruby-core:17615] [PATCH] ruby-mode.el: Fix here-doc 
>> strings with inner quotes"
>>     on Sat, 5 Jul 2008 17:57:32 +0900, Nathan Weizenbaum 
>> <[e-mail]> writes:
>> |
>> |[1  <text/plain; ISO-8859-1 (7bit)>]
>> |At the moment, ruby-mode.el uses font-lock-keywords as opposed to 
>> |font-lock-syntactic-keywords to highlight here-doc strings. This 
>> means |that Emacs doesn't actually recognize them as strings, so 
>> unbalanced |quotes paint the whole buffer in font-lock-string-face. 
>> In addition, it |improperly highlights strings that look like nested 
>> heredocs, like the |following:
>> |
>> |<<FOO
>> |<<BAR
>> |BAR
>> |FOO
>> |
>> |The attached patch uses font-lock-syntactic-keywords instead, so 
>> that |heredocs actually register as strings, so stray quotation marks 
>> don't |wreak havoc.
>>
>> I am not sure what this patch fixes.  But at least, the patched
>> version does not work well for the following code:
>>
>> print <<FOO, <<BAR
>> <<BAR
>> foo
>> FOO
>> bar
>> BAR
>>
>> it should highlight here-doc up to the last BAR.
>>
>>                             matz.
>>
>>
>>   
>