//! `TokenTree`s as well!
mod parser;
-mod mbe_expander;
+mod expander;
mod syntax_bridge;
mod tt_iter;
mod subtree_source;
#[cfg(test)]
mod tests;
+#[cfg(test)]
+mod benchmark;
+mod token_map;
+
use std::fmt;
pub use tt::{Delimiter, DelimiterKind, Punct};
use crate::{
- parser::{parse_pattern, parse_template, Op},
+ parser::{parse_pattern, parse_template, MetaTemplate, Op},
tt_iter::TtIter,
};
#[derive(Debug, PartialEq, Eq)]
pub enum ParseError {
+ UnexpectedToken(String),
Expected(String),
+ InvalidRepeat,
RepetitionEmptyTokenTree,
}
UnexpectedToken,
BindingError(String),
ConversionError,
- InvalidRepeat,
ProcMacroError(tt::ExpansionError),
UnresolvedProcMacro,
Other(String),
ExpandError::UnexpectedToken => f.write_str("unexpected token in input"),
ExpandError::BindingError(e) => f.write_str(e),
ExpandError::ConversionError => f.write_str("could not convert tokens"),
- ExpandError::InvalidRepeat => f.write_str("invalid repeat expression"),
ExpandError::ProcMacroError(e) => e.fmt(f),
ExpandError::UnresolvedProcMacro => f.write_str("unresolved proc macro"),
ExpandError::Other(e) => f.write_str(e),
}
}
-pub use crate::syntax_bridge::{
- ast_to_token_tree, parse_to_token_tree, syntax_node_to_token_tree, token_tree_to_syntax_node,
- TokenMap,
+pub use crate::{
+ syntax_bridge::{
+ ast_to_token_tree, parse_exprs_with_sep, parse_to_token_tree, syntax_node_to_token_tree,
+ token_tree_to_syntax_node,
+ },
+ token_map::TokenMap,
};
/// This struct contains AST for a single `macro_rules` definition. What might
shift: Shift,
}
+/// For Macro 2.0
#[derive(Clone, Debug, PartialEq, Eq)]
-struct Rule {
- lhs: MetaTemplate,
- rhs: MetaTemplate,
+pub struct MacroDef {
+ rules: Vec<Rule>,
+ /// Highest id of the token we have in TokenMap
+ shift: Shift,
}
#[derive(Clone, Debug, PartialEq, Eq)]
-struct MetaTemplate {
- delimiter: Option<Delimiter>,
- tokens: Vec<Result<Op, ExpandError>>,
-}
-
-impl<'a> MetaTemplate {
- fn iter(&self) -> impl Iterator<Item = &Result<Op, ExpandError>> {
- self.tokens.iter()
- }
-
- fn delimiter_kind(&self) -> Option<DelimiterKind> {
- self.delimiter.map(|it| it.kind)
- }
+struct Rule {
+ lhs: MetaTemplate,
+ rhs: MetaTemplate,
}
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
/// Shift given TokenTree token id
fn shift_all(self, tt: &mut tt::Subtree) {
- for t in tt.token_trees.iter_mut() {
+ for t in &mut tt.token_trees {
match t {
tt::TokenTree::Leaf(leaf) => match leaf {
tt::Leaf::Ident(ident) => ident.id = self.shift(ident.id),
let mut src = TtIter::new(tt);
let mut rules = Vec::new();
while src.len() > 0 {
- let rule = Rule::parse(&mut src)?;
+ let rule = Rule::parse(&mut src, true)?;
rules.push(rule);
if let Err(()) = src.expect_char(';') {
if src.len() > 0 {
}
}
- for rule in rules.iter() {
+ for rule in &rules {
validate(&rule.lhs)?;
}
// apply shift
let mut tt = tt.clone();
self.shift.shift_all(&mut tt);
- mbe_expander::expand(self, &tt)
+ expander::expand_rules(&self.rules, &tt)
+ }
+
+ pub fn map_id_down(&self, id: tt::TokenId) -> tt::TokenId {
+ self.shift.shift(id)
+ }
+
+ pub fn map_id_up(&self, id: tt::TokenId) -> (tt::TokenId, Origin) {
+ match self.shift.unshift(id) {
+ Some(id) => (id, Origin::Call),
+ None => (id, Origin::Def),
+ }
+ }
+}
+
+impl MacroDef {
+ pub fn parse(tt: &tt::Subtree) -> Result<MacroDef, ParseError> {
+ let mut src = TtIter::new(tt);
+ let mut rules = Vec::new();
+
+ if Some(tt::DelimiterKind::Brace) == tt.delimiter_kind() {
+ cov_mark::hit!(parse_macro_def_rules);
+ while src.len() > 0 {
+ let rule = Rule::parse(&mut src, true)?;
+ rules.push(rule);
+ if let Err(()) = src.expect_any_char(&[';', ',']) {
+ if src.len() > 0 {
+ return Err(ParseError::Expected(
+ "expected `;` or `,` to delimit rules".to_string(),
+ ));
+ }
+ break;
+ }
+ }
+ } else {
+ cov_mark::hit!(parse_macro_def_simple);
+ let rule = Rule::parse(&mut src, false)?;
+ if src.len() != 0 {
+ return Err(ParseError::Expected("remain tokens in macro def".to_string()));
+ }
+ rules.push(rule);
+ }
+ for rule in &rules {
+ validate(&rule.lhs)?;
+ }
+
+ Ok(MacroDef { rules, shift: Shift::new(tt) })
+ }
+
+ pub fn expand(&self, tt: &tt::Subtree) -> ExpandResult<tt::Subtree> {
+ // apply shift
+ let mut tt = tt.clone();
+ self.shift.shift_all(&mut tt);
+ expander::expand_rules(&self.rules, &tt)
}
pub fn map_id_down(&self, id: tt::TokenId) -> tt::TokenId {
}
impl Rule {
- fn parse(src: &mut TtIter) -> Result<Rule, ParseError> {
+ fn parse(src: &mut TtIter, expect_arrow: bool) -> Result<Self, ParseError> {
let lhs = src
.expect_subtree()
.map_err(|()| ParseError::Expected("expected subtree".to_string()))?;
- src.expect_char('=').map_err(|()| ParseError::Expected("expected `=`".to_string()))?;
- src.expect_char('>').map_err(|()| ParseError::Expected("expected `>`".to_string()))?;
+ if expect_arrow {
+ src.expect_char('=').map_err(|()| ParseError::Expected("expected `=`".to_string()))?;
+ src.expect_char('>').map_err(|()| ParseError::Expected("expected `>`".to_string()))?;
+ }
let rhs = src
.expect_subtree()
.map_err(|()| ParseError::Expected("expected subtree".to_string()))?;
- let lhs = MetaTemplate { tokens: parse_pattern(&lhs), delimiter: None };
- let rhs = MetaTemplate { tokens: parse_template(&rhs), delimiter: None };
+ let lhs = MetaTemplate(parse_pattern(lhs)?);
+ let rhs = MetaTemplate(parse_template(rhs)?);
Ok(crate::Rule { lhs, rhs })
}
}
-fn to_parse_error(e: &ExpandError) -> ParseError {
- let msg = match e {
- ExpandError::InvalidRepeat => "invalid repeat".to_string(),
- _ => "invalid macro definition".to_string(),
- };
- ParseError::Expected(msg)
-}
-
fn validate(pattern: &MetaTemplate) -> Result<(), ParseError> {
for op in pattern.iter() {
- let op = op.as_ref().map_err(|e| to_parse_error(&e))?;
-
match op {
- Op::Subtree(subtree) => validate(&subtree)?,
- Op::Repeat { subtree, separator, .. } => {
+ Op::Subtree { tokens, .. } => validate(tokens)?,
+ Op::Repeat { tokens: subtree, separator, .. } => {
// Checks that no repetition which could match an empty token
// https://github.com/rust-lang/rust/blob/a58b1ed44f5e06976de2bdc4d7dc81c36a96934f/src/librustc_expand/mbe/macro_rules.rs#L558
- if separator.is_none() {
- if subtree.iter().all(|child_op| {
- match child_op.as_ref().map_err(to_parse_error) {
- Ok(Op::Var { kind, .. }) => {
+ if separator.is_none()
+ && subtree.iter().all(|child_op| {
+ match child_op {
+ Op::Var { kind, .. } => {
// vis is optional
if kind.as_ref().map_or(false, |it| it == "vis") {
return true;
}
}
- Ok(Op::Repeat { kind, .. }) => {
+ Op::Repeat { kind, .. } => {
return matches!(
kind,
parser::RepeatKind::ZeroOrMore | parser::RepeatKind::ZeroOrOne
)
}
- _ => {}
+ Op::Leaf(_) => {}
+ Op::Subtree { .. } => {}
}
false
- }) {
- return Err(ParseError::RepetitionEmptyTokenTree);
- }
+ })
+ {
+ return Err(ParseError::RepetitionEmptyTokenTree);
}
validate(subtree)?
}
}
pub fn result(self) -> Result<T, ExpandError> {
- self.err.map(Err).unwrap_or(Ok(self.value))
+ self.err.map_or(Ok(self.value), Err)
}
}
impl<T: Default> From<Result<T, ExpandError>> for ExpandResult<T> {
fn from(result: Result<T, ExpandError>) -> Self {
- result.map_or_else(|e| Self::only_err(e), |it| Self::ok(it))
+ result.map_or_else(Self::only_err, Self::ok)
}
}