diff options
Diffstat (limited to 'src/libsyntax_pos')
| -rw-r--r-- | src/libsyntax_pos/hygiene.rs | 73 |
1 files changed, 44 insertions, 29 deletions
diff --git a/src/libsyntax_pos/hygiene.rs b/src/libsyntax_pos/hygiene.rs index b827416ab53..4dbd4ccda91 100644 --- a/src/libsyntax_pos/hygiene.rs +++ b/src/libsyntax_pos/hygiene.rs @@ -59,13 +59,12 @@ pub struct Mark(u32); #[derive(Clone, Debug)] struct MarkData { parent: Mark, - default_transparency: Transparency, expn_info: Option<ExpnInfo>, } /// A property of a macro expansion that determines how identifiers /// produced by that expansion are resolved. -#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Hash, Debug)] +#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Hash, Debug, RustcEncodable, RustcDecodable)] pub enum Transparency { /// Identifier produced by a transparent expansion is always resolved at call-site. /// Call-site spans in procedural macros, hygiene opt-out in `macro` should use this. @@ -85,12 +84,7 @@ pub enum Transparency { impl Mark { pub fn fresh(parent: Mark) -> Self { HygieneData::with(|data| { - data.marks.push(MarkData { - parent, - // By default expansions behave like `macro_rules`. - default_transparency: Transparency::SemiTransparent, - expn_info: None, - }); + data.marks.push(MarkData { parent, expn_info: None }); Mark(data.marks.len() as u32 - 1) }) } @@ -118,7 +112,7 @@ impl Mark { #[inline] pub fn expn_info(self) -> Option<ExpnInfo> { - HygieneData::with(|data| data.expn_info(self)) + HygieneData::with(|data| data.expn_info(self).cloned()) } #[inline] @@ -126,12 +120,6 @@ impl Mark { HygieneData::with(|data| data.marks[self.0 as usize].expn_info = Some(info)) } - #[inline] - pub fn set_default_transparency(self, transparency: Transparency) { - assert_ne!(self, Mark::root()); - HygieneData::with(|data| data.marks[self.0 as usize].default_transparency = transparency) - } - pub fn is_descendant_of(self, ancestor: Mark) -> bool { HygieneData::with(|data| data.is_descendant_of(self, ancestor)) } @@ -172,9 +160,8 @@ impl Mark { #[inline] pub fn looks_like_proc_macro_derive(self) -> bool { HygieneData::with(|data| { - let mark_data = &data.marks[self.0 as usize]; - if mark_data.default_transparency == Transparency::Opaque { - if let Some(expn_info) = &mark_data.expn_info { + if data.default_transparency(self) == Transparency::Opaque { + if let Some(expn_info) = &data.marks[self.0 as usize].expn_info { if let ExpnFormat::MacroAttribute(name) = expn_info.format { if name.as_str().starts_with("derive(") { return true; @@ -199,9 +186,6 @@ impl HygieneData { HygieneData { marks: vec![MarkData { parent: Mark::root(), - // If the root is opaque, then loops searching for an opaque mark - // will automatically stop after reaching it. - default_transparency: Transparency::Opaque, expn_info: None, }], syntax_contexts: vec![SyntaxContextData { @@ -220,8 +204,8 @@ impl HygieneData { GLOBALS.with(|globals| f(&mut *globals.hygiene_data.borrow_mut())) } - fn expn_info(&self, mark: Mark) -> Option<ExpnInfo> { - self.marks[mark.0 as usize].expn_info.clone() + fn expn_info(&self, mark: Mark) -> Option<&ExpnInfo> { + self.marks[mark.0 as usize].expn_info.as_ref() } fn is_descendant_of(&self, mut mark: Mark, ancestor: Mark) -> bool { @@ -235,7 +219,9 @@ impl HygieneData { } fn default_transparency(&self, mark: Mark) -> Transparency { - self.marks[mark.0 as usize].default_transparency + self.marks[mark.0 as usize].expn_info.as_ref().map_or( + Transparency::SemiTransparent, |einfo| einfo.default_transparency + ) } fn modern(&self, ctxt: SyntaxContext) -> SyntaxContext { @@ -427,7 +413,6 @@ impl SyntaxContext { HygieneData::with(|data| { data.marks.push(MarkData { parent: Mark::root(), - default_transparency: Transparency::SemiTransparent, expn_info: Some(expansion_info), }); @@ -613,7 +598,7 @@ impl SyntaxContext { /// `ctxt.outer().expn_info()`. #[inline] pub fn outer_expn_info(self) -> Option<ExpnInfo> { - HygieneData::with(|data| data.expn_info(data.outer(self))) + HygieneData::with(|data| data.expn_info(data.outer(self)).cloned()) } /// `ctxt.outer_and_expn_info()` is equivalent to but faster than @@ -622,7 +607,7 @@ impl SyntaxContext { pub fn outer_and_expn_info(self) -> (Mark, Option<ExpnInfo>) { HygieneData::with(|data| { let outer = data.outer(self); - (outer, data.expn_info(outer)) + (outer, data.expn_info(outer).cloned()) }) } @@ -651,6 +636,7 @@ impl fmt::Debug for SyntaxContext { /// Extra information for tracking spans of macro and syntax sugar expansion #[derive(Clone, Hash, Debug, RustcEncodable, RustcDecodable)] pub struct ExpnInfo { + // --- The part unique to each expansion. /// The location of the actual macro invocation or syntax sugar , e.g. /// `let x = foo!();` or `if let Some(y) = x {}` /// @@ -661,13 +647,18 @@ pub struct ExpnInfo { /// call_site span would have its own ExpnInfo, with the call_site /// pointing to the `foo!` invocation. pub call_site: Span, + /// The format with which the macro was invoked. + pub format: ExpnFormat, + + // --- The part specific to the macro/desugaring definition. + // --- FIXME: Share it between expansions with the same definition. /// The span of the macro definition itself. The macro may not /// have a sensible definition span (e.g., something defined /// completely inside libsyntax) in which case this is None. /// This span serves only informational purpose and is not used for resolution. pub def_site: Option<Span>, - /// The format with which the macro was invoked. - pub format: ExpnFormat, + /// Transparency used by `apply_mark` for mark with this expansion info by default. + pub default_transparency: Transparency, /// List of #[unstable]/feature-gated features that the macro is allowed to use /// internally without forcing the whole crate to opt-in /// to them. @@ -682,6 +673,30 @@ pub struct ExpnInfo { pub edition: Edition, } +impl ExpnInfo { + /// Constructs an expansion info with default properties. + pub fn default(format: ExpnFormat, call_site: Span, edition: Edition) -> ExpnInfo { + ExpnInfo { + call_site, + format, + def_site: None, + default_transparency: Transparency::SemiTransparent, + allow_internal_unstable: None, + allow_internal_unsafe: false, + local_inner_macros: false, + edition, + } + } + + pub fn with_unstable(format: ExpnFormat, call_site: Span, edition: Edition, + allow_internal_unstable: &[Symbol]) -> ExpnInfo { + ExpnInfo { + allow_internal_unstable: Some(allow_internal_unstable.into()), + ..ExpnInfo::default(format, call_site, edition) + } + } +} + /// The source of expansion. #[derive(Clone, Hash, Debug, PartialEq, Eq, RustcEncodable, RustcDecodable)] pub enum ExpnFormat { |