Mailing-List: contact dev-help@systemml.incubator.apache.org; run by ezmlm
Precedence: bulk
Reply-To: dev@systemml.incubator.apache.org
From: Matthias Boehm <mboehm7@googlemail.com>
Subject: Re: Standard code styles for DML and Java?
To: dev@systemml.incubator.apache.org
References: <CAO1aQR9fDBfOizjYSo51e6GXrcj8BLUkF86MdV8CJwDtR2r-3g@mail.gmail.com>
Message-ID: <1b749616-bc07-8996-1fe2-1629f9c1b97a@gmail.com>
Date: Tue, 2 May 2017 20:25:21 -0400
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101
 Thunderbird/45.4.0
MIME-Version: 1.0
In-Reply-To: <CAO1aQR9fDBfOizjYSo51e6GXrcj8BLUkF86MdV8CJwDtR2r-3g@mail.gmail.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
archived-at: Wed, 03 May 2017 00:25:29 -0000

thanks Deron for centralizing this discussion, as this could help to 
avoid redundancy spread across many individual JIRAs and PRs. Overall, I 
think it would be good to agree on individual style guides for DML and 
Java.

I'm fine with using spaces for DML scripts because they are rarely 
changed once written. However, for Java, I'd strongly prefer tabs for 
indentation because tabs are (1) faster to navigate, and (2) allow to 
configure the dev environment according to subjective preferences. For 
inline formatting both should use spaces though.

Finally, I would recommend to also include common inconsistency such as 
exception handling (catch all vs redundant error messages), 
hashcode/equals, unnecessary branches, etc.

Regards,
Matthias

On 5/2/2017 7:15 PM, Deron Eriksson wrote:
> Recently Matthias, Mike, and I discussed the issue of DML code style on
> SYSTEMML-1406 (https://issues.apache.org/jira/browse/SYSTEMML-1406). We
> also have an issue regarding Java code style on SYSTEMML-137 (
> https://issues.apache.org/jira/browse/SYSTEMML-137).
>
> In the discussion on SYSTEMML-1406, it sounds like Matthias, Mike, and I
> all see value in having a consistent style, although individual preferences
> differ. I would like to start a short discussion to see if we could apply
> common style standards to our Java and DML files.
>
> WRT Java, perhaps the Google Style Guide (
> https://google.github.io/styleguide/javaguide.html) would be a good place
> to start.
> https://github.com/google/styleguide/blob/gh-pages/eclipse-java-google-style.xml
> https://github.com/google/styleguide/blob/gh-pages/intellij-java-google-style.xml
>
> We could use these Eclipse/IntelliJ Java style templates as a base and
> modify them for any changes we agree upon (for example, tabs vs spaces for
> indentation). We could then check these templates into our project so that
> everyone who contributes to SystemML can apply the common style to code,
> thus adding consistency to the project.
>
> WRT DML, the main issue we discussed was tabs vs spaces for indentation.
>
> Some options I see are:
> 1) No official DML/Java styles
> 2) DML/Java styles (use spaces for indents, with style guide as basis for
> Java)
> 3) DML/Java styles (use tabs for indents, with style guide as basis for
> Java)
>
> Although I would prefer 2), I would be happy with 3) as an improvement from
> our existing 1). We could also have alternate options such as spaces for
> DML and tabs for Java.
>
> Thoughts?
> Deron
>