11475: Impr mbe: remove unecessary temporary vec r=bellau a=bellau

It's a micro optimization. I don't know if it's really necessary (less alloc is always better).

Co-authored-by: bellau <laurent.belmonte@gmail.com>
This commit is contained in:
bors[bot] 2022-02-15 09:36:22 +00:00 committed by GitHub
commit f0210f8a43
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23

View File

@ -437,11 +437,12 @@ macro_rules! try_push {
let mut new_item = item.clone();
new_item.bindings = bindings_builder.copy(&new_item.bindings);
new_item.dot.next();
let mut vars = Vec::new();
collect_vars(&mut vars, tokens);
for var in vars {
bindings_builder.push_empty(&mut new_item.bindings, &var);
}
collect_vars(
&mut |s| {
bindings_builder.push_empty(&mut new_item.bindings, &s);
},
tokens,
);
cur_items.push(new_item);
}
cur_items.push(MatchState {
@ -729,17 +730,16 @@ fn match_meta_var(kind: &str, input: &mut TtIter) -> ExpandResult<Option<Fragmen
input.expect_fragment(fragment).map(|it| it.map(Fragment::Tokens))
}
fn collect_vars(buf: &mut Vec<SmolStr>, pattern: &MetaTemplate) {
fn collect_vars(collector_fun: &mut impl FnMut(SmolStr), pattern: &MetaTemplate) {
for op in pattern.iter() {
match op {
Op::Var { name, .. } => buf.push(name.clone()),
Op::Var { name, .. } => collector_fun(name.clone()),
Op::Leaf(_) => (),
Op::Subtree { tokens, .. } => collect_vars(buf, tokens),
Op::Repeat { tokens, .. } => collect_vars(buf, tokens),
Op::Subtree { tokens, .. } => collect_vars(collector_fun, tokens),
Op::Repeat { tokens, .. } => collect_vars(collector_fun, tokens),
}
}
}
impl MetaTemplate {
fn iter_delimited<'a>(&'a self, delimited: Option<&'a tt::Delimiter>) -> OpDelimitedIter<'a> {
OpDelimitedIter { inner: &self.0, idx: 0, delimited }