user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

document attribute parsers better

Browse source
This commit is contained in:
Jana Dönszelmann 2025-06-11 16:10:47 +02:00
parent 8ce2287586
commit 34241e5397
No known key found for this signature in database
1 changed files with 9 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

9
compiler/rustc_attr_parsing/src/attributes/mod.rs
View file

@ -51,6 +51,9 @@ type AcceptMapping<T> = &'static [(&'static [Symbol], AcceptFn<T>)];
/// whether it has seen the attribute it has been looking for.
///
/// The state machine is automatically reset to parse attributes on the next item.
///
/// For a simpler attribute parsing interface, consider using [`SingleAttributeParser`]
/// or [`CombineAttributeParser`] instead.
pub(crate) trait AttributeParser: Default + 'static {
/// The symbols for the attributes that this parser is interested in.
///
@ -59,6 +62,12 @@ pub(crate) trait AttributeParser: Default + 'static {
/// The parser has gotten a chance to accept the attributes on an item,
/// here it can produce an attribute.
///
/// All finalize methods of all parsers are unconditionally called.
/// This means you can't unconditionally return `Some` here,
/// that'd be equivalent to unconditionally applying an attribute to
/// every single syntax item that could have attributes applied to it.
/// Your accept mappings should determine whether this returns something.
fn finalize(self, cx: &FinalizeContext<'_>) -> Option<AttributeKind>;
}