bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/mbe/src/expander/matcher.rs')
-rw-r--r--crates/mbe/src/expander/matcher.rs60
1 files changed, 59 insertions, 1 deletions
diff --git a/crates/mbe/src/expander/matcher.rs b/crates/mbe/src/expander/matcher.rs
index 7d8f97c775..06c21dfd70 100644
--- a/crates/mbe/src/expander/matcher.rs
+++ b/crates/mbe/src/expander/matcher.rs
@@ -63,7 +63,7 @@ use std::rc::Rc;
use crate::{
expander::{Binding, Bindings, Fragment},
- parser::{Op, OpDelimited, OpDelimitedIter, RepeatKind, Separator},
+ parser::{Op, RepeatKind, Separator},
tt_iter::TtIter,
ExpandError, MetaTemplate,
};
@@ -750,6 +750,64 @@ fn collect_vars(buf: &mut Vec<SmolStr>, pattern: &MetaTemplate) {
}
}
+impl MetaTemplate {
+ fn iter_delimited<'a>(&'a self, delimited: Option<&'a tt::Delimiter>) -> OpDelimitedIter<'a> {
+ OpDelimitedIter { inner: &self.0, idx: 0, delimited }
+ }
+}
+
+#[derive(Debug, Clone, Copy)]
+enum OpDelimited<'a> {
+ Op(&'a Op),
+ Open,
+ Close,
+}
+
+#[derive(Debug, Clone, Copy)]
+struct OpDelimitedIter<'a> {
+ inner: &'a [Op],
+ delimited: Option<&'a tt::Delimiter>,
+ idx: usize,
+}
+
+impl<'a> OpDelimitedIter<'a> {
+ fn is_eof(&self) -> bool {
+ let len = self.inner.len() + if self.delimited.is_some() { 2 } else { 0 };
+ self.idx >= len
+ }
+
+ fn peek(&self) -> Option<OpDelimited<'a>> {
+ match self.delimited {
+ None => self.inner.get(self.idx).map(OpDelimited::Op),
+ Some(_) => match self.idx {
+ 0 => Some(OpDelimited::Open),
+ i if i == self.inner.len() + 1 => Some(OpDelimited::Close),
+ i => self.inner.get(i - 1).map(OpDelimited::Op),
+ },
+ }
+ }
+
+ fn reset(&self) -> Self {
+ Self { inner: self.inner, idx: 0, delimited: self.delimited }
+ }
+}
+
+impl<'a> Iterator for OpDelimitedIter<'a> {
+ type Item = OpDelimited<'a>;
+
+ fn next(&mut self) -> Option<Self::Item> {
+ let res = self.peek();
+ self.idx += 1;
+ res
+ }
+
+ fn size_hint(&self) -> (usize, Option<usize>) {
+ let len = self.inner.len() + if self.delimited.is_some() { 2 } else { 0 };
+ let remain = len.saturating_sub(self.idx);
+ (remain, Some(remain))
+ }
+}
+
impl<'a> TtIter<'a> {
fn expect_separator(&mut self, separator: &Separator, idx: usize) -> bool {
let mut fork = self.clone();