[cl-interpol-devel] Support for Perl $1 and Makefile-like special variables

[Evgeniy Zhemchugov]

Dear cl-interpol developer(s),

I would like to use cl-interpol to parse strings containing Perl
subpattern variables like $1 and Makefile special variables like $<,
$^ etc. I also want statements like #?"$(f 5)" when
*optional-delimiters-p* is t to be expanded into something like

(with-output-to-string (#:string) (princ (f 5) #:string))

rather than

(with-output-to-string (#:string) (princ (progn f 5) #:string))

as they do now. (However, for better compatibility with Makefiles I
need to treat the case of the list made of a single element in a
special way, expanding it to the value of the corresponding variable.)
Overall, I would like to have better control over the read-form
function, maybe the possibility to supply my own one. Could you
install some hook there? I'd gladly do it myself and send you a patch
but I'm not sure which way is the best and whether you will accept
such a change at all. If you advice me some workaround that doesn't
involve modifying cl-interpol it would also be great. I just don't
want to fork or recreate the whole library because of a single
function.