:community and :rod don't compose well

[vemv]

Hi!

As you surely remember, I requested the ":rod" style, which other people came to appreciate. In fact, at my new job they happened to be using it!

However, it's also used in composition with the :community style, which is when issues arise.

We use lein-zprint, with a :style [:community :rod] Lein setting. While either of those individually work as intended, when composed, they yield a 1-space indentation:

;; one-space indentation!
(defn foo [x]
 (println x "Hello, World!")
 (println x "Hello, World!")
 (println x "Hello, World!"))

Since 1-space indentation is not the intended (or effective) style of either preset, it seems to represent a bug. And of course it's quite an inconvenience, since it will cause quite the discrepancy between editors' formatting and zprint's in this case.

For your consideration.

Cheers - V

[kkinnear]

Oh yes, I surely remember! I implemented an entirely new subsystem in no small part so that I could implement the :rod style. I've used it for several things since, but your request was the main reason I started down that path.

This is clearly a bug of some kind. I can reproduce it, thanks for the simple example. I'm out of time tonight, but I'll give it a good hard look first thing tomorrow. I'm hopeful that I can find some fix that doesn't require a new release, but rather some configuration tweaking, but I'll know for sure once I figure out the details.

[kkinnear]

The problem is that some function types are "arg" and some are "body", and the :guided function type is "arg". I need to also create a :guided-body function type. and I will do so in the next release.

However, when using guides, the actual function type is pretty much ignored (except the the arg/body distinction), and so we can replace the :guided function type with one that is considered a body function type, for example, :fn as a temporary expedient to getting your code to format the way that you want it to.

[Note -- you have to be using zprint 1.2.1 or 1.2.2 for the following to work for you. I could change these instructions to work with 1.2.0 if that is what you have to use, so let me know if you need that.]

I can see two, rather similar, ways to do this. One is to just ignore the :rod style and fix defn to have the right stuff. The other is to redefine the :rod style to do this, and continue to use the current styles you are using.

Here is where you just fix the :fn-map for defn directly:

 projects/zprint % ./zprintm-1.2.2 '{:style [:community] :fn-map {"defn" [:fn {:list {:option-fn (partial rodguide {:multi-arity-nl? true})}}]}}'  <cljfiles/i223.clj
(defn foo [x]
  (println x "Hello, World!")
  (println x "Hello, World!")
  (println x "Hello, World!"))

Here is where you redefine the :rod style in the :style-map, and then use it as your normally do:

√ projects/zprint % ./zprintm-1.2.2 '{:style [:community :rod] :style-map {:rod {:fn-map {"defn" [:fn {:list {:option-fn (partial rodguide {:multi-arity-nl? true})}}]}}}}'  <cljfiles/i223.clj
(defn foo [x]
  (println x "Hello, World!")
  (println x "Hello, World!")
  (println x "Hello, World!"))

This makes me glad that I did the work to allow you to define a style and invoke it in the same option map. That didn't just fall out.

Since you are using lein zprint (and I'm glad you mentioned that), it is a bit more complex. You can't put the :style-map definition in the :zprint { ... } key-value pair in your project.clj, since lein zprint doesn't know about guides as yet. I wasn't sure anyone even used lein zprint anymore, since the executables are so much faster and have pretty much the equivalent or more capability.

You can, however, place the :style-map definition of :rod in a .zprint.edn in your project (i.e., in the same directory as your project.clj) and then you can do one of the following:

• put :search-config? true in every user's ~/.zprintrc file
• put :search-config? true in your :zprint { ... } key-value pair in your project.clj.

I would recommend the second, as it means that you don't have to have every user mess with their probably non-existent ~/.zprintrc or ~/.zprint.edn files.

So, here is the .zprint.edn file you put in your project:

√ projects/zprint % more .zprint.edn
{:style-map
   {:rod {:fn-map
            {"defn"
               [:fn
                {:list
                   {:option-fn (partial rodguide {:multi-arity-nl? true})}}]}}}}

and you just add :search-config? true to the :zprint key in your project.clj. And you should be in business.

When 1.2.3 comes out, you can remove the .zprint.edn file and remove the :search-config? true from your project.clj, and it should all still work.

Let me know if you have any problems with this.

[vemv]

Thanks much!

Sounding great.

For clarity, in the next stable release will [:community :rod] work as intended? It would be great to keep composing two high-level directives.

[kkinnear]

Yes, in the next stable release, that I expect to be 1.2.3, [:community :rod] will compose correctly.

[kkinnear]

This is fixed in 1.2.3. Thanks for noticing it and submitting an issue.

[vemv]

Awesome! Most likely I'll be giving it use asap.

Obviously I'll keep an eye open on #229 also - feel free to keep me in the loop.

[vemv]

Fix works like a charm!