Rollup merge of #127748 - scottmcm:option_len, r=joboet · model-checking/verify-rust-std@d1d9893 (original) (raw)
`@@ -770,6 +770,13 @@ impl Option {
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`}
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`}
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#[inline]
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const fn len(&self) -> usize {
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// Using the intrinsic avoids emitting a branch to get the 0 or 1.
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let discriminant: isize = crate::intrinsics::discriminant_value(self);
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discriminant as usize
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}
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`` /// Returns a slice of the contained value, if any. If this is None, an
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`/// empty slice is returned. This can be useful to have a single type of
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`` /// iterator over an Option or slice.
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`@@ -812,7 +819,7 @@ impl Option {
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`unsafe {
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` slice::from_raw_parts(
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`(self as *const Self).byte_add(core::mem::offset_of!(Self, Some.0)).cast(),
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`-
self.is_some() as usize,
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self.len(),
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`)
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`}
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`}
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`@@ -869,7 +876,7 @@ impl Option {
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`unsafe {
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` slice::from_raw_parts_mut(
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`(self as *mut Self).byte_add(core::mem::offset_of!(Self, Some.0)).cast(),
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`-
self.is_some() as usize,
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self.len(),
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`)
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`}
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`}
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`@@ -2242,10 +2249,8 @@ impl Iterator for Item {
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`#[inline]
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`fn size_hint(&self) -> (usize, Option) {
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`-
match self.opt {
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Some(_) => (1, Some(1)),
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None => (0, Some(0)),
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}
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let len = self.len();
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(len, Some(len))
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`}
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`}
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`@@ -2256,7 +2261,12 @@ impl DoubleEndedIterator for Item {
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`}
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`}
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`-
impl ExactSizeIterator for Item {}
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impl ExactSizeIterator for Item {
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#[inline]
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fn len(&self) -> usize {
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self.opt.len()
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}
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}
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`impl FusedIterator for Item {}
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`unsafe impl TrustedLen for Item {}
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``