use crate::priv_prelude::*;
#[derive(Clone, Debug)]
pub struct ItemUse {
pub visibility: Option<PubToken>,
pub use_token: UseToken,
pub root_import: Option<DoubleColonToken>,
pub tree: UseTree,
pub semicolon_token: SemicolonToken,
}
impl Spanned for ItemUse {
fn span(&self) -> Span {
let start = match &self.visibility {
Some(pub_token) => pub_token.span(),
None => self.use_token.span(),
};
let end = self.semicolon_token.span();
Span::join(start, end)
}
}
#[derive(Clone, Debug)]
pub enum UseTree {
Group {
imports: Braces<Punctuated<UseTree, CommaToken>>,
},
Name {
name: Ident,
},
Rename {
name: Ident,
as_token: AsToken,
alias: Ident,
},
Glob {
star_token: StarToken,
},
Path {
prefix: Ident,
double_colon_token: DoubleColonToken,
suffix: Box<UseTree>,
},
}
impl Parse for UseTree {
fn parse(parser: &mut Parser) -> ParseResult<UseTree> {
if let Some(imports) = Braces::try_parse(parser)? {
return Ok(UseTree::Group { imports });
}
if let Some(star_token) = parser.take() {
return Ok(UseTree::Glob { star_token });
}
let name = match parser.take() {
Some(name) => name,
None => return Err(parser.emit_error(ParseErrorKind::ExpectedImportNameGroupOrGlob)),
};
if let Some(as_token) = parser.take() {
let alias = parser.parse()?;
return Ok(UseTree::Rename {
name,
as_token,
alias,
});
}
if let Some(double_colon_token) = parser.take() {
let suffix = parser.parse()?;
return Ok(UseTree::Path {
prefix: name,
double_colon_token,
suffix,
});
}
Ok(UseTree::Name { name })
}
}
impl Parse for ItemUse {
fn parse(parser: &mut Parser) -> ParseResult<ItemUse> {
let visibility = parser.take();
let use_token = parser.parse()?;
let root_import = parser.take();
let tree = parser.parse()?;
let semicolon_token = parser.parse()?;
Ok(ItemUse {
visibility,
use_token,
root_import,
tree,
semicolon_token,
})
}
}