Distinguish between quoted and unquoted strings

[h-3-0]

Say that I have the function foo and the following sass

h1::before {
    content: foo()
}

What might I want foo to return? I either want what libsass considers to be an unquoted string, e.g. open-quote, or a quoted string, e.g. 'foo'.

Similarly, if a function takes a string as a parameter, it should be able to distinguish between foo(foo) and foo('foo').

Mirroring how libsass works (where quoted is a boolean field of Sass_String), I'm thinking of adding a parameter to the SassString data constructor like so

data SassValue = SassString Quoted String
    ...
    
data Quoted = Quoted | Unquoted

and adding support for this in hlibsass.

[jakubfijalkowski]

I'm trying to remember why I decided to ignore the quoted/unquoted distinction, because I do remember that I wasn't sure what to do about it. My only guess is that I haven't seen any valid usage for unquoted strings, especially at hsass level. I still don't get what the difference is, but I don't do front-end dev much these days, so could you point me to some explanation or explain me what is the benefit of using unquoted strings over quoted ones?

[h-3-0]

On the CSS side of things,

h1::before {
    content: open-quote
}

and

h1::before {
    content: 'open-quote'
}

mean different things (the first places open quotes before headings, the second literally prefixes headings with the string 'open-quote'). That was my motivation in creating this issue.

However, I misunderstood how libsass actually works. I've tested it now — the boring details are here. This behaviour might be familiar to you, but to summarise, a function taking a string can only determine if it is quoted by inspecting the quoted field. But when returning a string, the quoted field seems not to matter, and libsass will render the string exactly according to its value (so sass_make_qstring("open-quote") is rendered without quotes). Confusing, unless I'm missing something!

So, for the user of hsass, you can effectively produce quoted and unquoted strings, but you can't tell if a string that you're consuming is quoted or not. I don't actually have a use case for determining if a function's argument is quoted or not, so I don't mind if you consider this behaviour acceptable and close the issue.

It would still be possible to make this more consistant on the hsass/hlibsass side of things (I'd be tempted to define data SassValue = SassString String | SassKeyword String | ... since I think string vs. keyword is more clear than quoted string vs. unquoted string) but it would mean less closely mirroring the way libsass works. I don't know if that would be an improvement.