When I introduced the 'ser_de' feature, I couldn't find a way to
name it 'serde' while also make it pull the optional 'serde'
crate together with the other related dependencies.
With rustc >= 1.60 we can use 'dep:serde' to refer to the 'serde'
dependency as part of the 'serde' feature.
AudioCapsBuilder::new() will have the default values for
rate/channels/layout/format. Similarly, VideoCapsBuilder::new() will
have the default values for format/width/height/framerate.
The trait FormattedValue was only implemented on types which
could implement the full range of values for a Format. In order
to declare a function which could take both the intrinsic type
of any Format (e.g. `ClockTime`) as well the full range of values
(e.g. `Option<ClockTime>`), the argument was declared:
```rust
impl Into<GenericFormattedValue>,
```
This commit implements `FormattedValue` for any type representing
a format. E.g.: both `ClockTime` and `Option<ClockTime>` will now
implement `FormattedValue`. The trait `FormattedValueFullRange`
is implemented on types which can be built from any raw value.
These changes are intended to help for the implementation of a
means to enforce format conformity at compilation time for
functions with multiple formatted value arguments.
The following signatures were found to be incorrect and are fixed:
- `message::StepDone`: forced the type for `amount` and `duration`
to be of the same type, when `duration` is expected to be of the
`Time` format.
- `query::Convert::set`: the two arguments were forced to the same
type, so potentialy the same format, unless a
`GenericFormattedValue` was used.
See https://gitlab.freedesktop.org/gstreamer/gstreamer-rs/-/merge_requests/1059
Represents combinations of flags with a '+' separated string of nicks,
or an empty string for no flags set.
Note that most flag types will ignore any flags using multiple bits when
serializing, since in most cases these flags cover all used bits.
Feature flags are additive and a higher feature might be enabled by some
other dependency, which then can cause code that assumes the other API
fail to compile.
Still implement the constructor separately per version to make it clear
to the compiler that the constructor can't fail at all in newer
versions.
