Add feature to evaluate list around point

[gveres]

This adds a new function cider-eval-list-at-point, that evaluates a list around point [as in: code delimited by the nearest pair of parens surrounding point]. This comes handy to evaluate a function call while the point is anywhere within the function call.
It's modelled after the eval-sexp-at-point solution, and as such, deals with the "deref @" and other quirks intelligently.

In terms of the implementation, it's built on a thingatpoint built-in feature, so no magic text manipulation is happening. Although the thingatpoint code targets Emacs Lisp, it should work fine with Clojure code too.

Sorry, no tests (yet) - I'd appreciate some help or guidance on what to cover for this.

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Thanks!

If you're just starting out to hack on CIDER you might find this section of its
manual extremely useful.

[bbatsov]

Isn't cider-eval-sexp-at-point pretty much the same?

[gveres]

Isn't cider-eval-sexp-at-point pretty much the same?

No: as I understand, a symbol is also a sexp in the implementation, so if point is on a symbol, that symbol gets evaluated, not the surrounding list. list-at-point will expand to include the innermost surrounding paren pair, and sends that whole thing ("compound form"?) to eval.

[bbatsov]

Yeah, I think you're right. I use only eval-last-sexp and eval-defun, so my memory on everything else is fuzzy. I'll merge this as is and I'll add a couple of tests myself. Thanks!

[gveres]

Amazing - thanks a lot, @bbatsov!