This more concrete wrapper type can write a prefix the very first time something
is written to it. This allows removing plenty of useless monomorphisations caused
by the former W/SequenceWriter<W> pair of types.
This will allow #19659 to use derive on display using:
#[parse(aliases = "-webkit-flex")]
Flex,
#[parse(aliases = "-webkit-inline-flex")]
InlineFlex,
And such.
style: Move text-align outside of the mako file.
I will need this refactoring before my next job. I didn't actually fix the FIXME's along the way. My other PR probably will cover these.
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
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The trait ToAnimatedZero now supports it, and it now applies to things with generics,
avoiding the trait bounds for field types of the variant on which it applies.
For the traits we derive which methods don't depend on associated types (i.e.
all of them but ToAnimatedValue and ToComputedValue), we now add trait bounds
for the actual field types directly, instead of bounding the type parameters.
For now, only #[animation(error)] is supported on variants and it makes
both #[derive(Animate)] and #[derive(ComputeSquaredDistance)] ignore
this particular variant.
We simply implement ToCss for Option<T>, printing nothing if the value is None,
and we then use SequenceWriter to skip writing of separators around empty parts.
For now, only impls for types like in style::values::generics can be derived.
This also needed a few ToComputedValueAsSpecified impls that I would like to
replace by some #[to_computed_value(clone)] attribute, but I think it is ok
to keep it like this for now.
