Struct MetaItemParser 

pub struct MetaItemParser {
    path: OwnedPathParser,
    args: ArgParser,
    args_checked: AtomicBool,
}

Utility that deconstructs a MetaItem into usable parts.

MetaItems are syntactically extremely flexible, but specific attributes want to parse them in custom, more restricted ways. This can be done using this struct.

MetaItems consist of some path, and some args. The args could be empty. In other words:

• name -> args are empty
• name(...) -> args are a list, which is the bit between the parentheses
• name = value-> arg is name_value, where the argument is the = value part

The syntax of MetaItems can be found at https://doc.rust-lang.org/reference/attributes.html

Fields

path: OwnedPathParser

args: ArgParser

args_checked: AtomicBool

Whether the args of this meta item have been looked at. This is tracked because if the arguments of a MetaItemParser are ignored, this is probably a mistake

Implementations

impl MetaItemParser

pub fn ident(&self) -> Option<Ident>

For a single-segment meta item, returns its name; otherwise, returns None.

pub fn span(&self) -> Span

pub fn path(&self) -> &OwnedPathParser

Gets just the path, without the args. Some examples:

• #[rustfmt::skip]: rustfmt::skip is a path
• #[allow(clippy::complexity)]: clippy::complexity is a path
• #[inline]: inline is a single segment path

pub fn args(&self) -> &ArgParser

Gets just the args parser, without caring about the path.

pub fn word_is(&self, sym: Symbol) -> Option<&ArgParser>

Asserts that this MetaItem starts with a word, or single segment path.

Some examples:

• #[inline]: inline is a word
• #[rustfmt::skip]: rustfmt::skip is a path, and not a word and should instead be parsed using path

pub fn ignore_args(&self)

Explicitly ignore the arguments, disarming the arguments-used check

pub fn are_args_checked(&self) -> bool

Trait Implementations

impl Debug for MetaItemParser

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl ExpectNameValue for MetaItemParser

type Output<'a> = (Ident, &'a NameValueParser)

fn expect_name_value<'a, 'f, 'sess>( &'a self, cx: &mut AcceptContext<'f, 'sess>, _span: Span, name: Option<Symbol>, ) -> Option<Self::Output<'a>>

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 88 bytes