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Adjusted PR to better match project's coding style.

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This commit is contained in:
Vincent Esche
2016-01-22 17:13:17 +01:00
parent 70692ce279
commit 2c7a19a10d
1 changed files with 38 additions and 40 deletions
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78
src/librustc/middle/check_match.rs
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@@ -616,7 +616,8 @@ fn missing_constructors(cx: &MatchCheckCtxt, &Matrix(ref rows): &Matrix,
.collect(); .collect();
all_constructors(cx, left_ty, max_slice_length) all_constructors(cx, left_ty, max_slice_length)
.into_iter() .into_iter()
.filter(|c| !used_constructors.contains(c)).collect() .filter(|c| !used_constructors.contains(c))
.collect()
} }
/// This determines the set of all possible constructors of a pattern matching /// This determines the set of all possible constructors of a pattern matching
@@ -695,47 +696,44 @@ fn is_useful(cx: &MatchCheckCtxt,
let constructors = pat_constructors(cx, v[0], left_ty, max_slice_length); let constructors = pat_constructors(cx, v[0], left_ty, max_slice_length);
if constructors.is_empty() { if constructors.is_empty() {
match &missing_constructors(cx, matrix, left_ty, max_slice_length)[..] { let constructors = missing_constructors(cx, matrix, left_ty, max_slice_length);
[] => { if constructors.is_empty() {
all_constructors(cx, left_ty, max_slice_length).into_iter().map(|c| { all_constructors(cx, left_ty, max_slice_length).into_iter().map(|c| {
match is_useful_specialized(cx, matrix, v, c.clone(), left_ty, witness) { match is_useful_specialized(cx, matrix, v, c.clone(), left_ty, witness) {
UsefulWithWitness(pats) => UsefulWithWitness({ UsefulWithWitness(pats) => UsefulWithWitness({
let arity = constructor_arity(cx, &c, left_ty); let arity = constructor_arity(cx, &c, left_ty);
let mut result = { let mut result = {
let pat_slice = &pats[..]; let pat_slice = &pats[..];
let subpats: Vec<_> = (0..arity).map(|i| { let subpats: Vec<_> = (0..arity).map(|i| {
pat_slice.get(i).map_or(DUMMY_WILD_PAT, |p| &**p) pat_slice.get(i).map_or(DUMMY_WILD_PAT, |p| &**p)
}).collect(); }).collect();
vec![construct_witness(cx, &c, subpats, left_ty)] vec![construct_witness(cx, &c, subpats, left_ty)]
}; };
result.extend(pats.into_iter().skip(arity)); result.extend(pats.into_iter().skip(arity));
result result
}), }),
result => result
}
}).find(|result| result != &NotUseful).unwrap_or(NotUseful)
},
[constructors..] => {
let matrix = rows.iter().filter_map(|r| {
if pat_is_binding_or_wild(&cx.tcx.def_map.borrow(), raw_pat(r[0])) {
Some(r[1..].to_vec())
} else {
None
}
}).collect();
match is_useful(cx, &matrix, &v[1..], witness) {
UsefulWithWitness(pats) => {
let mut new_pats: Vec<_> = constructors.into_iter().map(|constructor| {
let arity = constructor_arity(cx, &constructor, left_ty);
let wild_pats = vec![DUMMY_WILD_PAT; arity];
construct_witness(cx, &constructor, wild_pats, left_ty)
}).collect();
new_pats.extend(pats);
UsefulWithWitness(new_pats)
},
result => result result => result
} }
}).find(|result| result != &NotUseful).unwrap_or(NotUseful)
} else {
let matrix = rows.iter().filter_map(|r| {
if pat_is_binding_or_wild(&cx.tcx.def_map.borrow(), raw_pat(r[0])) {
Some(r[1..].to_vec())
} else {
None
}
}).collect();
match is_useful(cx, &matrix, &v[1..], witness) {
UsefulWithWitness(pats) => {
let mut new_pats: Vec<_> = constructors.into_iter().map(|constructor| {
let arity = constructor_arity(cx, &constructor, left_ty);
let wild_pats = vec![DUMMY_WILD_PAT; arity];
construct_witness(cx, &constructor, wild_pats, left_ty)
}).collect();
new_pats.extend(pats);
UsefulWithWitness(new_pats)
},
result => result
} }
} }
} else { } else {