Rebol extension changes to languages.yml

[draegtun]

Historically Rebol used the .r extension which unfortunately clashes with the R Stats programming language :(

For example even the Rebol interpreter repo says it uses 9.7% R instead of Rebol! - https://github.com/rebol/rebol

So 3 changes here…

1. .reb is now the primary (and official) extension - http://www.rebol.com/article/0540.html

2. .rebol moved to list of extensions (some code does use it)

3. .r added back. NB. The majority of Rebol code on Rebol uses this (followed by .r2 & .r3). .r was present in languages.yml previously but was removed for some reason? (looks like here - 5a5d334)

[pchaigno]

Could you add samples for the file extensions you added?

[draegtun]

Added sample files with all the Rebol file extensions.

NB. They all display correct syntax highlighting except for .reb sample file. However I do have some examples in my repo where .r doesn't highlight correctly, for eg. https://github.com/draegtun/PrettifyRebol/blob/master/build/GCP-datatypes.r

[qtxie]

@pchaigno All Rebol source file MUST have a header. (docs: http://www.rebol.com/docs/core23/rebolcore-5.html#section-2), like this one:
Simplest form

REBOL []

Or this one:
Have more information

REBOL [
    Title:  "Scan Web Sites"
    Date:   2-Feb-2000
    File:   %webscan.r
    Author: "Jane Doer"
    Version: 1.2.3
]

So if the linguist is smart enough (search the header), no matter what extensions Rebol file used, linguist can recognize it, and distinguish it from R language easily.

[pchaigno]

It would be better to have the .r file that isn't recognized as Rebol as a sample.
For the header, I don't think linguist is smart enough :/ (will see once you added the GCP-datatypes file).
However, you can help it by adding some heuristics (using REBOL) in heuristics.rb

[draegtun]

Will this be enough @pchaigno ?

[pchaigno]

I tested your branch on two repositories: rebol and one of yours (PrettifyRebol).
Some Rebol files were still detected as R files.
To make it work, I had to change a bit the heuristics and I replaced the Rebol sample files with "real" ones from the two repositories (see my branch).

Do you want to make the changes or should I open a new pull request?

(The Travis build failed on all the last pull requests so don't worry about it.)

[draegtun]

I've made the changes you've suggested to my patch to keep everything together (see above).

Many thanks for all your help on this @pchaigno. Fingers crossed this now does the business :)

[qtxie]

@pchaigno The project red is also a good test for Rebol. Now it shows the project use 97.1% R, but actually it is not use even one line R !

[earl]

May I venture to suggest some more example scripts to better train the classifier:

• (Rebol) Red/System's lexer: https://github.com/red/red/blob/master/lexer.r (BSD licensed)
• (Rebol) A trivial and a bit stupid http server: https://github.com/earl/rebol3/blob/master/scripts/shttpd.r (Apache licensed)
• (Rebol) Another Rebol syntax highlighting script: https://github.com/rgchris/Scripts/blob/master/color-code.r (Apache licensed)
• (R) plyr's join function: https://github.com/hadley/plyr/blob/master/R/join.r (MIT licensed)

[pchaigno]

You should regenerate samples.json if you want the new sample files to be used in the statistical classifier.

[draegtun]

@pchaigno Sorry for the delay. I had some issues getting my Ruby env up-to-date to run bundler/rake on linguist repo (in the end I had to start from clean slate). Passes Travis so hopefully this is now all good to go.

[arfon]

Just a quick update. I've merged these changes in here. If there are still some issues with misidentification then perhaps we can add some more samples and even consider a heuristic that picks up on REBOL