Description
I would like some clarification on some issues, I was recently looking at min, max, clamp functions and in my naive estimation of how they work they should be able to take as a parameter any thing that results in a value with a unit of measurement.
In the browsers I have tested you can of course use values that come from functions inside of other functions, thus you can use the result of a calc in a variable inside a min function.
Many different properties where math functions are usable have special value keywords - for example max-content, min-content in width.
Or something like the fit-content function.
In my naive consideration it seemed obvious to me that max-content can be used inside of a min function, given that fit-content is described as fit-content(stretch) i.e. min(max-content, max(min-content, stretch)) in css-sizing-4, that is to say I thought of fit-content as a bit of syntactical sugar so that developers if they wanted fit-content functionality wouldn't have to write it themselves all the time, or more to the point that clamp was a bit of syntactical sugar for an operation that developers might want to do, as is implied by example 31 of css-values-4 which says:
An occasional point of confusion when using min()/max() is that you use max() to impose a minimum value on something (that is, properties like min-width effectively use max()), and min() to impose a maximum value on something; it’s easy to accidentally reach for the opposite function and try to use min() to add a minimum size. Using clamp() can make the code read more naturally, as the value is nestled between its minimum and maximum:
.type {
/* Force the font-size to stay between 12px and 100px */
font-size: clamp(12px, 10 * (1vw + 1vh) / 2, 100px);
}
Following this naive consideration I expected that if doing min(max-content - 10px, 200px) it should figure out what max-content is in the context used and perform the calculations, but in testing neither Mozilla nor Chrome do this - I raised an issue on bugzilla just to hear if they could point me out that there was a part of the specs I was unfamiliar with that meant my expectations were totally out of whack https://bugzilla.mozilla.org/show_bug.cgi?id=1667306 where it was suggested I raise the issue here in order to be able to define how it should work.
As was noted in the discussion about the bug-report this would open up interesting animation possibilities, the more I think about it I can see uses (for specifically max-content) in utility classes that can be added to parts of a subtree to calculate out their size in the relation of what encloses them. But really it seems a point of clarity to have every keyword that returns a value potentially consumable by a function at a particular property should actually be consumable by the function - since min-content and max-content return lengths those keywords should be able to be passed as properties to whatever function we want to use to set the width.