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nikomatsakiscsmoe
nikomatsakis
and
csmoe
committed
change to 0-based indices
Co-authored-by: csmoe <35686186+csmoe@users.noreply.github.com>
1 parent 22a25d9 commit 783fe4f

14 files changed

+27
-27
lines changed

‎src/librustc/ty/sty.rs‎

Lines changed: 12 additions & 12 deletions
Original file line numberDiff line numberDiff line change
@@ -989,11 +989,11 @@ impl<'a, 'gcx, 'tcx> ParamTy {
989989
/// for<'a> fn(for<'b> fn(&'b isize, &'a isize), &'a char)
990990
/// ^ ^ | | |
991991
/// | | | | |
992-
/// | +------------+ 1 | |
992+
/// | +------------+ 0 | |
993993
/// | | |
994-
/// +--------------------------------+ 2 |
994+
/// +--------------------------------+ 1 |
995995
/// | |
996-
/// +------------------------------------------+ 1
996+
/// +------------------------------------------+ 0
997997
///
998998
/// In this type, there are two binders (the outer fn and the inner
999999
/// fn). We need to be able to determine, for any given region, which
@@ -1005,9 +1005,9 @@ impl<'a, 'gcx, 'tcx> ParamTy {
10051005
///
10061006
/// Let's start with the reference type `&'b isize` that is the first
10071007
/// argument to the inner function. This region `'b` is assigned a De
1008-
/// Bruijn index of 1, meaning "the innermost binder" (in this case, a
1008+
/// Bruijn index of 0, meaning "the innermost binder" (in this case, a
10091009
/// fn). The region `'a` that appears in the second argument type (`&'a
1010-
/// isize`) would then be assigned a De Bruijn index of 2, meaning "the
1010+
/// isize`) would then be assigned a De Bruijn index of 1, meaning "the
10111011
/// second-innermost binder". (These indices are written on the arrays
10121012
/// in the diagram).
10131013
///
@@ -1017,15 +1017,15 @@ impl<'a, 'gcx, 'tcx> ParamTy {
10171017
/// the outermost fn. But this time, this reference is not nested within
10181018
/// any other binders (i.e., it is not an argument to the inner fn, but
10191019
/// rather the outer one). Therefore, in this case, it is assigned a
1020-
/// De Bruijn index of 1, because the innermost binder in that location
1020+
/// De Bruijn index of 0, because the innermost binder in that location
10211021
/// is the outer fn.
10221022
///
10231023
/// [dbi]: http://en.wikipedia.org/wiki/De_Bruijn_index
10241024
#[derive(Clone, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, Debug, Copy, PartialOrd, Ord)]
10251025
pub struct DebruijnIndex {
10261026
/// We maintain the invariant that this is never 0. So 1 indicates
10271027
/// the innermost binder.
1028-
depth: u32,
1028+
index: u32,
10291029
}
10301030

10311031
pub type Region<'tcx> = &'tcx RegionKind;
@@ -1259,7 +1259,7 @@ impl<'a, 'tcx, 'gcx> PolyExistentialProjection<'tcx> {
12591259
}
12601260

12611261
impl DebruijnIndex {
1262-
pub const INNERMOST: DebruijnIndex = DebruijnIndex { depth: 1 };
1262+
pub const INNERMOST: DebruijnIndex = DebruijnIndex { index: 0 };
12631263

12641264
/// Returns the resulting index when this value is moved into
12651265
/// `amount` number of new binders. So e.g. if you had
@@ -1273,7 +1273,7 @@ impl DebruijnIndex {
12731273
/// you would need to shift the index for `'a` into 1 new binder.
12741274
#[must_use]
12751275
pub const fn shifted_in(self, amount: u32) -> DebruijnIndex {
1276-
DebruijnIndex { depth: self.depth + amount }
1276+
DebruijnIndex { index: self.index + amount }
12771277
}
12781278

12791279
/// Update this index in place by shifting it "in" through
@@ -1286,7 +1286,7 @@ impl DebruijnIndex {
12861286
/// `amount` number of new binders.
12871287
#[must_use]
12881288
pub const fn shifted_out(self, amount: u32) -> DebruijnIndex {
1289-
DebruijnIndex { depth: self.depth - amount }
1289+
DebruijnIndex { index: self.index - amount }
12901290
}
12911291

12921292
/// Update in place by shifting out from `amount` binders.
@@ -1315,12 +1315,12 @@ impl DebruijnIndex {
13151315
/// bound by one of the binders we are shifting out of, that is an
13161316
/// error (and should fail an assertion failure).
13171317
pub fn shifted_out_to_binder(self, to_binder: DebruijnIndex) -> Self {
1318-
self.shifted_out(to_binder.depth - Self::INNERMOST.depth)
1318+
self.shifted_out(to_binder.index - Self::INNERMOST.index)
13191319
}
13201320
}
13211321

13221322
impl_stable_hash_for!(struct DebruijnIndex {
1323-
depth
1323+
index
13241324
});
13251325

13261326
/// Region utilities

‎src/test/ui/nll/closure-requirements/escape-argument-callee.stderr‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -18,7 +18,7 @@ LL | let mut closure = expect_sig(|p, y| *p = y);
1818
|
1919
= note: defining type: DefId(0/1:9 ~ escape_argument_callee[317d]::test[0]::{{closure}}[0]) with closure substs [
2020
i16,
21-
for<'r, 's, 't0> extern "rust-call" fn((&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) mut &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) i32, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't0)) i32))
21+
for<'r, 's, 't0> extern "rust-call" fn((&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) mut &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) i32, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't0)) i32))
2222
]
2323

2424
note: No external requirements

‎src/test/ui/nll/closure-requirements/escape-argument.stderr‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -6,7 +6,7 @@ LL | let mut closure = expect_sig(|p, y| *p = y);
66
|
77
= note: defining type: DefId(0/1:9 ~ escape_argument[317d]::test[0]::{{closure}}[0]) with closure substs [
88
i16,
9-
for<'r, 's> extern "rust-call" fn((&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) mut &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) i32, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) i32))
9+
for<'r, 's> extern "rust-call" fn((&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) mut &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) i32, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) i32))
1010
]
1111

1212
note: No external requirements

‎src/test/ui/nll/closure-requirements/propagate-approximated-fail-no-postdom.stderr‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -24,7 +24,7 @@ LL | | },
2424
|
2525
= note: defining type: DefId(0/1:20 ~ propagate_approximated_fail_no_postdom[317d]::supply[0]::{{closure}}[0]) with closure substs [
2626
i16,
27-
for<'r, 's> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&'_#2r &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) &'_#3r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>))
27+
for<'r, 's> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&'_#2r &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) &'_#3r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>))
2828
]
2929

3030
note: No external requirements

‎src/test/ui/nll/closure-requirements/propagate-approximated-ref.stderr‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -18,7 +18,7 @@ LL | | });
1818
|
1919
= note: defining type: DefId(0/1:18 ~ propagate_approximated_ref[317d]::supply[0]::{{closure}}[0]) with closure substs [
2020
i16,
21-
for<'r, 's, 't0, 't1, 't2, 't3> extern "rust-call" fn((&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't0)) std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't1)) &'_#2r u32>, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't2)) std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't3)) std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't1)) u32>))
21+
for<'r, 's, 't0, 't1, 't2, 't3> extern "rust-call" fn((&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't0)) std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't1)) &'_#2r u32>, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't2)) std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't3)) std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't1)) u32>))
2222
]
2323
= note: number of external vids: 3
2424
= note: where '_#1r: '_#2r

‎src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-comparing-against-free.stderr‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -23,7 +23,7 @@ LL | | })
2323
|
2424
= note: defining type: DefId(0/1:12 ~ propagate_approximated_shorter_to_static_comparing_against_free[317d]::case1[0]::{{closure}}[0]) with closure substs [
2525
i32,
26-
for<'r> extern "rust-call" fn((std::cell::Cell<&'_#1r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>))
26+
for<'r> extern "rust-call" fn((std::cell::Cell<&'_#1r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>))
2727
]
2828

2929
note: No external requirements
@@ -51,7 +51,7 @@ LL | | })
5151
|
5252
= note: defining type: DefId(0/1:13 ~ propagate_approximated_shorter_to_static_comparing_against_free[317d]::case2[0]::{{closure}}[0]) with closure substs [
5353
i32,
54-
for<'r> extern "rust-call" fn((std::cell::Cell<&'_#1r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>))
54+
for<'r> extern "rust-call" fn((std::cell::Cell<&'_#1r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>))
5555
]
5656
= note: number of external vids: 2
5757
= note: where '_#1r: '_#0r

‎src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-no-bound.stderr‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -18,7 +18,7 @@ LL | | });
1818
|
1919
= note: defining type: DefId(0/1:18 ~ propagate_approximated_shorter_to_static_no_bound[317d]::supply[0]::{{closure}}[0]) with closure substs [
2020
i16,
21-
for<'r, 's, 't0, 't1, 't2> extern "rust-call" fn((&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't0)) std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't1)) std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't2)) u32>))
21+
for<'r, 's, 't0, 't1, 't2> extern "rust-call" fn((&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't0)) std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't1)) std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't2)) u32>))
2222
]
2323
= note: number of external vids: 2
2424
= note: where '_#1r: '_#0r

‎src/test/ui/nll/closure-requirements/propagate-approximated-shorter-to-static-wrong-bound.stderr‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -18,7 +18,7 @@ LL | | });
1818
|
1919
= note: defining type: DefId(0/1:18 ~ propagate_approximated_shorter_to_static_wrong_bound[317d]::supply[0]::{{closure}}[0]) with closure substs [
2020
i16,
21-
for<'r, 's, 't0, 't1, 't2, 't3> extern "rust-call" fn((&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't0)) std::cell::Cell<&'_#2r &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't1)) u32>, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't2)) std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't3)) std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 't1)) u32>))
21+
for<'r, 's, 't0, 't1, 't2, 't3> extern "rust-call" fn((&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't0)) std::cell::Cell<&'_#2r &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't1)) u32>, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't2)) std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>, &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't3)) std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 't1)) u32>))
2222
]
2323
= note: number of external vids: 3
2424
= note: where '_#1r: '_#0r

‎src/test/ui/nll/closure-requirements/propagate-approximated-val.stderr‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -18,7 +18,7 @@ LL | | });
1818
|
1919
= note: defining type: DefId(0/1:18 ~ propagate_approximated_val[317d]::test[0]::{{closure}}[0]) with closure substs [
2020
i16,
21-
for<'r, 's> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) &'_#2r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>))
21+
for<'r, 's> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) &'_#2r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>))
2222
]
2323
= note: number of external vids: 3
2424
= note: where '_#1r: '_#2r

‎src/test/ui/nll/closure-requirements/propagate-despite-same-free-region.stderr‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -16,7 +16,7 @@ LL | | },
1616
|
1717
= note: defining type: DefId(0/1:16 ~ propagate_despite_same_free_region[317d]::supply[0]::{{closure}}[0]) with closure substs [
1818
i16,
19-
for<'r, 's> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) &'_#2r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { depth: 1 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>))
19+
for<'r, 's> extern "rust-call" fn((std::cell::Cell<&'_#1r &ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) &'_#2r u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 'r)) u32>, std::cell::Cell<&ReLateBound(DebruijnIndex { index: 0 }, BrNamed(crate0:DefIndex(0:0), 's)) u32>))
2020
]
2121
= note: number of external vids: 3
2222
= note: where '_#1r: '_#2r

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