Checking in string constants fails for elm, Haskell, & PureScript

[mzero]

All three languages, elm, haskell, purescript have standard style quoted strings using double quotes:

"I am a string with a speeling misteek."

elm and purescript also support multi-line strings with triple quotes:

"""
If monads are like burrrritos
Can I put salza on them?
"""

All three languages are described by one entry in lib/doctype.js:

        case 'elm':
        case 'haskell':
        case 'purescript':
            return new Code_1.default({ comment_start: '{-', comment_end: '-}', comment_line: '--' });

But that entry only describes comments. That entry probably needs to be split into two (one for elm & purescript, one for haskell) - like so:

        case 'elm':
        case 'purescript':
            return new Code_1.default({ comment_start: '{-', comment_end: '-}', comment_line: '--', string_inline: '"', string_quote: '\\', string_multiline: '"""'});
        case 'haskell':
            return new Code_1.default({ comment_start: '{-', comment_end: '-}', comment_line: '--', string_inline: '"', string_quote: '\\'});

I would test that... but don't have the environment to build and test VCS extensions.