60 lines
1.6 KiB
Rust
60 lines
1.6 KiB
Rust
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// check-pass
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fn nop(_s: &[& i32]) {}
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fn nop_subslice(_s: &[i32]) {}
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fn const_index_ok(s: &mut [i32]) {
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if let [ref first, ref second, _, ref fourth, ..] = *s {
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if let [_, _, ref mut third, ..] = *s {
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nop(&[first, second, third, fourth]);
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}
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}
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}
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fn const_index_from_end_ok(s: &mut [i32]) {
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if let [.., ref fourth, ref third, _, ref first] = *s {
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if let [.., ref mut second, _] = *s {
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nop(&[first, second, third, fourth]);
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}
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}
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}
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fn const_index_mixed(s: &mut [i32]) {
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if let [.., _, ref from_end4, ref from_end3, _, ref from_end1] = *s {
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if let [ref mut from_begin0, ..] = *s {
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nop(&[from_begin0, from_end1, from_end3, from_end4]);
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}
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}
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if let [ref from_begin0, ref from_begin1, _, ref from_begin3, _, ..] = *s {
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if let [.., ref mut from_end1] = *s {
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nop(&[from_begin0, from_begin1, from_begin3, from_end1]);
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}
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}
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}
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fn const_index_and_subslice_ok(s: &mut [i32]) {
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if let [ref first, ref second, ..] = *s {
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if let [_, _, ref mut tail @ ..] = *s {
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nop(&[first, second]);
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nop_subslice(tail);
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}
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}
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}
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fn const_index_and_subslice_from_end_ok(s: &mut [i32]) {
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if let [.., ref second, ref first] = *s {
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if let [ref mut tail @ .., _, _] = *s {
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nop(&[first, second]);
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nop_subslice(tail);
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}
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}
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}
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fn main() {
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let mut v = [1,2,3,4];
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const_index_ok(&mut v);
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const_index_from_end_ok(&mut v);
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const_index_and_subslice_ok(&mut v);
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const_index_and_subslice_from_end_ok(&mut v);
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}
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