Writing code as string with syntax highlighting

Question

I am trying to write a ruby source code as a string (as part of real Ruby code) on a text editor with syntax highlighting for Ruby code, but want the Ruby syntax highlighting to work on the code inside the string. Using double or single quotes, percent notation, heredoc all make the text editor recognize that it is a string, so the whole chunk of code is colored in a single color as a string.

<<_
class Foo
    def bar
        # blah blah
    end
end
_

Is there a way to let the Ruby syntax highlighting on the editor miss the borders of the string so that its content is highlightened as Ruby code?

Edit

Stefan notices a wonderful feature on Atom, Sublime Text and RubyMine to do this. But unfortunately, it does not seem to work on Emacs ruby mode. Does someone know of a modified ruby-mode.el or a some additional library on emacs to do this?

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Or can anyone write a simple elisp code (just to ignore heredoc start and end when the heredoc identifier is RUBY if it is difficult to implement highlighting for other languages)?

Using RUBY (or HTML or SQL) as the heredoc identifier works in some editors, i.e. str = <<-RUBY — Stefan
You should be able to set that up using mmm-mode, but that will require some tinkering. — Dmitry

Stefan Stefan · Accepted Answer · 2014-10-26T13:05:56

At least Atom, Sublime Text and RubyMine support syntax highlighting based on the heredoc identifier. <<-RUBY is rendered as Ruby, <<-SQL as SQL and so on.

Here's a screenshot from Atom:

Atom Editor Screenshot

Writing code as string with syntax highlighting

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2 Answers