Re: RFC 226 (v2) Selective interpolation in single quotish context.

[Philip Newton]

On 15 Sep 2000, at 1:10, Perl6 RFC Librarian wrote:

> With this proposal, the scalar C<$filename> can be tagged to be interpolated
> by the C<\I...\E> pair and the double quotish context replaced by single
> quotish context resulting in the following:

Definitely with this change, you should include a section on 
COMPATIBILITY, noting that people might be using \I in single-quoted 
strings already -- this would break. For example, some misguided 
DOS user with a filename such as C:\INCLUDE\SYS$HEADER\ERRNO.H 
(horribly contrived, I know -- not even sure whether $ is legal in a 
DOS path, but I think it is) might be surprised if he got an error 
message about $HEADER being undef.

What about \Itext\E, where text does not contain a scalar? Is this the 
same as "text"? How about \Ibefore${var}after\E -- is that the same 
as "before${var}after"? Does @foo interpolate inside \I...\E? (With 
join $"?) What about backslashes inside \I...\E (as in the above funny 
filename)?

Cheers,
Philip