Struct StripUnconfigured

pub struct StripUnconfigured<'a> {
    pub sess: &'a Session,
    pub features: Option<&'a Features>,
    pub config_tokens: bool,
    pub lint_node_id: NodeId,
}

A folder that strips out items that do not belong in the current configuration.

Fields

sess: &'a Session

features: Option<&'a Features>

config_tokens: bool

If true, perform cfg-stripping on attached tokens. This is only used for the input to derive macros, which needs eager expansion of cfg and cfg_attr

lint_node_id: NodeId

Implementations

impl<'a> StripUnconfigured<'a>

pub fn configure<T: HasAttrs + HasTokens>(&self, node: T) -> Option<T>

fn try_configure_tokens<T: HasTokens>(&self, node: &mut T)

fn configure_tokens(&self, stream: &AttrTokenStream) -> AttrTokenStream

Performs cfg-expansion on stream, producing a new AttrTokenStream. This is only used during the invocation of derive proc-macros, which require that we cfg-expand their entire input. Normal cfg-expansion operates on parsed AST nodes via the configure method

fn process_cfg_attrs<T: HasAttrs>(&self, node: &mut T)

Parse and expand all cfg_attr attributes into a list of attributes that are within each cfg_attr that has a true configuration predicate.

Gives compiler warnings if any cfg_attr does not contain any attributes and is in the original source code. Gives compiler errors if the syntax of any cfg_attr is incorrect.

fn process_cfg_attr(&self, attr: &Attribute) -> Vec<Attribute>

pub(crate) fn expand_cfg_attr( &self, cfg_attr: &Attribute, recursive: bool, ) -> Vec<Attribute>

Parse and expand a single cfg_attr attribute into a list of attributes when the configuration predicate is true, or otherwise expand into an empty list of attributes.

Gives a compiler warning when the cfg_attr contains no attributes and is in the original source file. Gives a compiler error if the syntax of the attribute is incorrect.

fn expand_cfg_attr_item( &self, cfg_attr: &Attribute, (item, item_span): (AttrItem, Span), ) -> Attribute

fn in_cfg(&self, attrs: &[Attribute]) -> bool

Determines if a node with the given attributes should be included in this configuration.

pub(crate) fn cfg_true(&self, attr: &Attribute) -> (bool, Option<MetaItem>)

pub(crate) fn maybe_emit_expr_attr_err(&self, attr: &Attribute)

If attributes are not allowed on expressions, emit an error for attr

pub fn configure_expr(&self, expr: &mut P<Expr>, method_receiver: bool)

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: 24 bytes