Create declarative macro for EBML Elements #125
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This makes the Element ID a fixed part of the Error. The ID can probably be turned into an `Option<NonZeroU32>` at some point, but that feels like a low priority.
- Refactor ebml_generic for better readability - Add lifetime parameter to EbmlParsable This allows implementing the trait for borrowed types like &[u8] (binary_ref). - Add `fn has_crc() -> bool` to trait EbmlParsable Also adds CRC-32 capabilities to ebml_generic, making it functionally equivalent to the master helper function when has_crc returns true. - Rename ebml_generic to ebml_element It can now handle most EBML Elements without issue, so the new name is more descriptive.
**This breaks compilation for elements.rs**, because matroska_permutation was changed (again) and it's not worth fixing this when the macros can soon be used instead. The macro `impl_ebml_master` will 1. create a pub struct definition with the given field names/types and any meta (like #[derive] blocks) and 2. implement EbmlParsable for the aforementioned struct. This implementation will set the has_crc() to true (to use the new ebml_element feature) and create a try_parse definition based on matroska_permutation. It will auto-"unwrap" the parser results and handle any parsing errors. It also handles Option<T> and Vec<T>.
There's no such thing as "single-element tuples", so the macro-implemented `impl Permutation` blocks don't work for singular Parser functions. So, here's a manual implementation.
- Use impl_ebml_master to define all Matroska Master Elements - Change sub_element helper to make it similar to ebml_element, but still work in the SegmentElement context. - Adapt segment_element fn to the sub_element changes. - Add note to fix what used to be correct Float Element handling (used to be float_or) - Small fix in the macro (lifetime-related) - Comment out/remove the unimplemented Elements Chapters, Tags, Attachments and Cues (should be added back later) - Edit serializer/muxer/demuxer stuff so it works again after the changes
Luni-4
requested changes
Apr 21, 2023
They were pub before (and in the crate root).
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This fixes a bug introduced in #123 (see the first commit on this branch).
Float handling (see #116) has regressed since float_or can't currently be used. This should be fixable, but I didn't want to push even more things into the branch.
Something should also be done about the
TrackEntryfield stream_index. It shouldn't really be in that struct since it's not part of the Matroska format. That has an easy workaround though, so it's not very important.Should also get macro-specific tests at some point.