From 7279749bbb0888f265a7ebdcffeff10c0fc88154 Mon Sep 17 00:00:00 2001 From: Edwin Cheng Date: Sun, 14 Mar 2021 11:52:58 +0800 Subject: Simpify mbe bindings builder --- crates/mbe/src/expander/matcher.rs | 120 ++++++++++++++++++------------------- 1 file changed, 57 insertions(+), 63 deletions(-) (limited to 'crates') diff --git a/crates/mbe/src/expander/matcher.rs b/crates/mbe/src/expander/matcher.rs index 54db76d5d..2c69e8968 100644 --- a/crates/mbe/src/expander/matcher.rs +++ b/crates/mbe/src/expander/matcher.rs @@ -162,9 +162,9 @@ struct BindingsBuilder { impl BindingsBuilder { fn alloc(&mut self) -> BindingsIdx { let idx = self.nodes.len(); - self.nodes.push(Vec::with_capacity(8)); + self.nodes.push(Vec::new()); let nidx = self.nested.len(); - self.nested.push(Vec::with_capacity(8)); + self.nested.push(Vec::new()); BindingsIdx(idx, nidx) } @@ -182,11 +182,8 @@ impl BindingsBuilder { if len < 4 { target.push(target[idx].clone()) } else { - let mut item = Vec::with_capacity(8); - item.push(LinkNode::Parent { idx, len }); - target.push(item); + target.push(vec![LinkNode::Parent { idx, len }]); } - new_idx } } @@ -212,19 +209,22 @@ impl BindingsBuilder { fn push_default(&mut self, idx: &mut BindingsIdx) { self.nested[idx.1].push(LinkNode::Node(idx.0)); let new_idx = self.nodes.len(); - self.nodes.push(Vec::with_capacity(8)); + self.nodes.push(Vec::new()); idx.0 = new_idx; } fn build(self, idx: &BindingsIdx) -> Bindings { let mut bindings = Bindings::default(); - self.build_recur(&mut bindings, self.nodes[idx.0].clone()); + self.build_inner(&mut bindings, &self.nodes[idx.0]); bindings } - fn build_recur(&self, bindings: &mut Bindings, nodes: Vec>>) { - for cmd in self.flatten_nodes(nodes) { - match &*cmd { + fn build_inner(&self, bindings: &mut Bindings, link_nodes: &Vec>>) { + let mut nodes = Vec::new(); + self.collect_nodes(&link_nodes, &mut nodes); + + for cmd in nodes { + match &**cmd { BindingKind::Empty(name) => { bindings.push_empty(name); } @@ -234,10 +234,11 @@ impl BindingsBuilder { BindingKind::Fragment(name, fragment) => { bindings.inner.insert(name.clone(), Binding::Fragment(fragment.clone())); } - BindingKind::Nested(idx, list) => { - let list = self.flatten_nested(*idx, *list); + BindingKind::Nested(idx, nested_idx) => { + let mut nested_nodes = Vec::new(); + self.collect_nested(*idx, *nested_idx, &mut nested_nodes); - for (idx, iter) in list.enumerate() { + for (idx, iter) in nested_nodes.into_iter().enumerate() { for (key, value) in &iter.inner { let bindings = bindings .inner @@ -258,62 +259,55 @@ impl BindingsBuilder { } } - fn flatten_nested_ref(&self, id: usize, len: usize) -> Vec>>> { - self.nested[id] - .iter() - .take(len) - .map(|it| match it { - LinkNode::Node(id) => vec![self.nodes[*id].clone()], - LinkNode::Parent { idx, len } => self.flatten_nested_ref(*idx, *len), - }) - .flatten() - .collect() + fn collect_nested_ref<'a>( + &'a self, + id: usize, + len: usize, + nested_refs: &mut Vec<&'a Vec>>>, + ) { + self.nested[id].iter().take(len).for_each(|it| match it { + LinkNode::Node(id) => nested_refs.push(&self.nodes[*id]), + LinkNode::Parent { idx, len } => self.collect_nested_ref(*idx, *len, nested_refs), + }); } - fn flatten_nested<'a>( - &'a self, - idx: usize, - list: usize, - ) -> impl Iterator + 'a { - let last = self.nodes[idx].clone(); - self.nested[list] - .iter() - .map(move |it| match *it { - LinkNode::Node(idx) => vec![self.nodes[idx].clone()], - LinkNode::Parent { idx, len } => self.flatten_nested_ref(idx, len), - }) - .flatten() - .chain(std::iter::once(last)) - .map(move |iter| { - let mut child_bindings = Bindings::default(); - self.build_recur(&mut child_bindings, iter); - child_bindings - }) + fn collect_nested(&self, idx: usize, nested_idx: usize, nested: &mut Vec) { + let last = &self.nodes[idx]; + let mut nested_refs = Vec::new(); + self.nested[nested_idx].iter().for_each(|it| match *it { + LinkNode::Node(idx) => nested_refs.push(&self.nodes[idx]), + LinkNode::Parent { idx, len } => self.collect_nested_ref(idx, len, &mut nested_refs), + }); + nested_refs.push(last); + + nested_refs.into_iter().for_each(|iter| { + let mut child_bindings = Bindings::default(); + self.build_inner(&mut child_bindings, &iter); + nested.push(child_bindings) + }) } - fn flatten_nodes_ref(&self, id: usize, len: usize) -> Vec> { - self.nodes[id] - .iter() - .take(len) - .map(|it| match it { - LinkNode::Node(it) => vec![it.clone()], - LinkNode::Parent { idx, len } => self.flatten_nodes_ref(*idx, *len), - }) - .flatten() - .collect() + fn collect_nodes_ref<'a>( + &'a self, + id: usize, + len: usize, + nodes: &mut Vec<&'a Rc>, + ) { + self.nodes[id].iter().take(len).for_each(|it| match it { + LinkNode::Node(it) => nodes.push(it), + LinkNode::Parent { idx, len } => self.collect_nodes_ref(*idx, *len, nodes), + }); } - fn flatten_nodes<'a>( + fn collect_nodes<'a>( &'a self, - nodes: Vec>>, - ) -> impl Iterator> + 'a { - nodes - .into_iter() - .map(move |it| match it { - LinkNode::Node(it) => vec![it], - LinkNode::Parent { idx, len } => self.flatten_nodes_ref(idx, len), - }) - .flatten() + link_nodes: &'a Vec>>, + nodes: &mut Vec<&'a Rc>, + ) { + link_nodes.into_iter().for_each(|it| match it { + LinkNode::Node(it) => nodes.push(it), + LinkNode::Parent { idx, len } => self.collect_nodes_ref(*idx, *len, nodes), + }); } } -- cgit v1.2.3