bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/mbe/src/expander/transcriber.rs')
-rw-r--r--crates/mbe/src/expander/transcriber.rs50
1 files changed, 46 insertions, 4 deletions
diff --git a/crates/mbe/src/expander/transcriber.rs b/crates/mbe/src/expander/transcriber.rs
index 9fccf5f424..d1bcf3dbcc 100644
--- a/crates/mbe/src/expander/transcriber.rs
+++ b/crates/mbe/src/expander/transcriber.rs
@@ -131,8 +131,9 @@ pub(super) fn transcribe<S: Span>(
template: &MetaTemplate<S>,
bindings: &Bindings<S>,
marker: impl Fn(&mut S) + Copy,
+ new_meta_vars: bool,
) -> ExpandResult<tt::Subtree<S>> {
- let mut ctx = ExpandCtx { bindings, nesting: Vec::new() };
+ let mut ctx = ExpandCtx { bindings, nesting: Vec::new(), new_meta_vars };
let mut arena: Vec<tt::TokenTree<S>> = Vec::new();
expand_subtree(&mut ctx, template, None, &mut arena, marker)
}
@@ -152,6 +153,7 @@ struct NestingState {
struct ExpandCtx<'a, S> {
bindings: &'a Bindings<S>,
nesting: Vec<NestingState>,
+ new_meta_vars: bool,
}
fn expand_subtree<S: Span>(
@@ -232,6 +234,21 @@ fn expand_subtree<S: Span>(
.into(),
);
}
+ Op::Length { depth } => {
+ let length = ctx.nesting.get(ctx.nesting.len() - 1 - depth).map_or(0, |_nest| {
+ // FIXME: to be implemented
+ 0
+ });
+ arena.push(
+ tt::Leaf::Literal(tt::Literal {
+ text: length.to_string().into(),
+ // FIXME
+ #[allow(deprecated)]
+ span: S::DUMMY,
+ })
+ .into(),
+ );
+ }
Op::Count { name, depth } => {
let mut binding = match ctx.bindings.get(name.as_str()) {
Ok(b) => b,
@@ -269,7 +286,13 @@ fn expand_subtree<S: Span>(
}
}
- let c = match count(ctx, binding, 0, *depth) {
+ let res = if ctx.new_meta_vars {
+ count(ctx, binding, 0, depth.unwrap_or(0))
+ } else {
+ count_old(ctx, binding, 0, *depth)
+ };
+
+ let c = match res {
Ok(c) => c,
Err(e) => {
// XXX: It *might* make sense to emit a dummy integer value like `0` here.
@@ -518,14 +541,33 @@ fn fix_up_and_push_path_tt<S: Span>(buf: &mut Vec<tt::TokenTree<S>>, subtree: tt
fn count<S>(
ctx: &ExpandCtx<'_, S>,
binding: &Binding<S>,
+ depth_curr: usize,
+ depth_max: usize,
+) -> Result<usize, CountError> {
+ match binding {
+ Binding::Nested(bs) => {
+ if depth_curr == depth_max {
+ Ok(bs.len())
+ } else {
+ bs.iter().map(|b| count(ctx, b, depth_curr + 1, depth_max)).sum()
+ }
+ }
+ Binding::Empty => Ok(0),
+ Binding::Fragment(_) | Binding::Missing(_) => Ok(1),
+ }
+}
+
+fn count_old<S>(
+ ctx: &ExpandCtx<'_, S>,
+ binding: &Binding<S>,
our_depth: usize,
count_depth: Option<usize>,
) -> Result<usize, CountError> {
match binding {
Binding::Nested(bs) => match count_depth {
- None => bs.iter().map(|b| count(ctx, b, our_depth + 1, None)).sum(),
+ None => bs.iter().map(|b| count_old(ctx, b, our_depth + 1, None)).sum(),
Some(0) => Ok(bs.len()),
- Some(d) => bs.iter().map(|b| count(ctx, b, our_depth + 1, Some(d - 1))).sum(),
+ Some(d) => bs.iter().map(|b| count_old(ctx, b, our_depth + 1, Some(d - 1))).sum(),
},
Binding::Empty => Ok(0),
Binding::Fragment(_) | Binding::Missing(_) => {