Struct extent::Extent

source · 
pub struct Extent<N: PrimInt> { /* private fields */ }

Implementations§

Returns the number of values included in this extent, as a usize, if the elements of the extent and the quantity of values between them, inclusively, can all be represented exactly as a usize. Various conditions may make this impossible: if the extent uses a numeric type larger than a usize, for example, or even if it includes the entire range of possible usize values (the quantity of which are a number one greater than the largest representable usize). This function also returns None for any extents involving negatve values of signed types (some such cases could still be represented as usize differences from lo-to-hi, but it is fussy to get the cases all right and this is not the main use-case for this library).

Same as len() but targeting u64 rather than usize. Depending on use-case, some contexts prefer measuring extents against a definite-sized type.

Examples found in repository?
src/lib.rs (line 67)
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    fn default() -> Self {
        Self::empty()
    }
}

impl<N: PrimInt> Extent<N> {
    pub fn lo(&self) -> Option<N> {
        if self.is_empty() {
            None
        } else {
            Some(self.lo)
        }
    }

    pub fn hi(&self) -> Option<N> {
        if self.is_empty() {
            None
        } else {
            Some(self.hi)
        }
    }

    pub unsafe fn lo_unchecked(&self) -> N {
        self.lo
    }

    pub unsafe fn hi_unchecked(&self) -> N {
        self.hi
    }

    /// Returns the number of values included in this extent, as a usize, if the
    /// elements of the extent _and_ the quantity of values between them,
    /// inclusively, can all be represented exactly as a usize. Various
    /// conditions may make this impossible: if the extent uses a numeric type
    /// larger than a usize, for example, or even if it includes the entire
    /// range of possible usize values (the quantity of which are a number one
    /// greater than the largest representable usize). This function also
    /// returns None for any extents involving negatve values of signed types
    /// (some such cases could still be represented as usize _differences_ from
    /// lo-to-hi, but it is fussy to get the cases all right and this is not the
    /// main use-case for this library).
    pub fn len(&self) -> Option<usize> {
        if self.is_empty() {
            Some(0)
        } else if let (Some(lo), Some(hi)) = (self.lo.to_usize(), self.hi.to_usize()) {
            let exclusive_range: usize = hi - lo;
            if exclusive_range < usize::MAX {
                Some(exclusive_range + 1)
            } else {
                None
            }
        } else {
            None
        }
    }

    /// Same as len() but targeting u64 rather than usize. Depending on
    /// use-case, some contexts prefer measuring extents against a
    /// definite-sized type.
    pub fn len_u64(&self) -> Option<u64> {
        if self.is_empty() {
            Some(0)
        } else if let (Some(lo), Some(hi)) = (self.lo.to_u64(), self.hi.to_u64()) {
            let exclusive_range: u64 = hi - lo;
            if exclusive_range < u64::MAX {
                Some(exclusive_range + 1)
            } else {
                None
            }
        } else {
            None
        }
    }

    pub fn empty() -> Self {
        Self {
            lo: N::one(),
            hi: N::zero(),
        }
    }

    pub fn is_empty(&self) -> bool {
        self.lo > self.hi
    }

    pub fn new<T: Borrow<N>, U: Borrow<N>>(lo: T, hi: U) -> Self {
        let lo: N = *lo.borrow();
        let hi: N = *hi.borrow();
        Self {
            lo: lo.min(hi),
            hi: hi.max(lo),
        }
    }

    pub unsafe fn new_unchecked<T: Borrow<N>, U: Borrow<N>>(lo: T, hi: U) -> Self {
        let lo: N = *lo.borrow();
        let hi: N = *hi.borrow();
        if lo > hi {
            Self::empty()
        } else {
            Self { lo, hi }
        }
    }

    pub fn union<S: Borrow<Self>>(&self, other: S) -> Self {
        if self.is_empty() {
            *other.borrow()
        } else if other.borrow().is_empty() {
            self.clone()
        } else {
            let other = *other.borrow();
            Self::new(self.lo.min(other.lo), self.hi.max(other.hi))
        }
    }

    pub fn intersect<S: Borrow<Self>>(&self, other: S) -> Self {
        if self.is_empty() || other.borrow().is_empty() {
            Extent::empty()
        } else {
            let other = *other.borrow();
            Self::new(&self.lo.max(other.lo), &self.hi.min(other.hi))
        }
    }

    pub fn contains<T: Borrow<N>>(&self, n: T) -> bool {
        let n = *n.borrow();
        self.lo <= n && n <= self.hi
    }

    pub fn iter(&self) -> ExtentIter<N> {
        ExtentIter(*self)
    }
}

#[derive(Clone, Debug, Default)]
pub struct ExtentIter<N: PrimInt>(Extent<N>);

impl<N: PrimInt> Iterator for ExtentIter<N> {
    type Item = N;

    fn next(&mut self) -> Option<Self::Item> {
        if self.0.is_empty() {
            None
        } else {
            let v = self.0.lo;
            self.0.lo = self.0.lo + N::one();
            Some(v)
        }
    }
}

impl<N: PrimInt> ExtentIter<N> {
    pub fn rev(self) -> ExtentRevIter<N> {
        ExtentRevIter(self.0)
    }
}

pub struct ExtentRevIter<N: PrimInt>(Extent<N>);

impl<N: PrimInt> Iterator for ExtentRevIter<N> {
    type Item = N;

    fn next(&mut self) -> Option<Self::Item> {
        if self.0.is_empty() {
            None
        } else {
            let v = self.0.hi;
            self.0.hi = self.0.hi - N::one();
            Some(v)
        }
    }
}

// std::ops::Range is an exclusive range. Extent is inclusive,
// so we subtract one from any nonempty std::ops::Range.
impl<N: PrimInt> From<Range<N>> for Extent<N> {
    fn from(r: Range<N>) -> Self {
        if r.is_empty() {
            Self::empty()
        } else {
            Self {
                lo: r.start,
                hi: r.end - N::one(),
            }
        }
    }
}

impl<N: PrimInt> TryFrom<Extent<N>> for Range<N> {
    type Error = &'static str;
    fn try_from(e: Extent<N>) -> Result<Self, Self::Error> {
        if e.is_empty() {
            Ok(Range {
                start: N::zero(),
                end: N::zero(),
            })
        } else if e.hi == N::max_value() {
            Err("Extent.hi is N::max_value(), can't represent as Range")
        } else {
            Ok(Range {
                start: e.lo,
                end: e.hi + N::one(),
            })
        }
    }
}

impl<N: PrimInt> From<RangeInclusive<N>> for Extent<N> {
    fn from(r: RangeInclusive<N>) -> Self {
        if r.is_empty() {
            Self::empty()
        } else {
            Self::new(r.start(), r.end())
        }
    }
Examples found in repository?
src/lib.rs (line 73)
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    pub fn lo(&self) -> Option<N> {
        if self.is_empty() {
            None
        } else {
            Some(self.lo)
        }
    }

    pub fn hi(&self) -> Option<N> {
        if self.is_empty() {
            None
        } else {
            Some(self.hi)
        }
    }

    pub unsafe fn lo_unchecked(&self) -> N {
        self.lo
    }

    pub unsafe fn hi_unchecked(&self) -> N {
        self.hi
    }

    /// Returns the number of values included in this extent, as a usize, if the
    /// elements of the extent _and_ the quantity of values between them,
    /// inclusively, can all be represented exactly as a usize. Various
    /// conditions may make this impossible: if the extent uses a numeric type
    /// larger than a usize, for example, or even if it includes the entire
    /// range of possible usize values (the quantity of which are a number one
    /// greater than the largest representable usize). This function also
    /// returns None for any extents involving negatve values of signed types
    /// (some such cases could still be represented as usize _differences_ from
    /// lo-to-hi, but it is fussy to get the cases all right and this is not the
    /// main use-case for this library).
    pub fn len(&self) -> Option<usize> {
        if self.is_empty() {
            Some(0)
        } else if let (Some(lo), Some(hi)) = (self.lo.to_usize(), self.hi.to_usize()) {
            let exclusive_range: usize = hi - lo;
            if exclusive_range < usize::MAX {
                Some(exclusive_range + 1)
            } else {
                None
            }
        } else {
            None
        }
    }

    /// Same as len() but targeting u64 rather than usize. Depending on
    /// use-case, some contexts prefer measuring extents against a
    /// definite-sized type.
    pub fn len_u64(&self) -> Option<u64> {
        if self.is_empty() {
            Some(0)
        } else if let (Some(lo), Some(hi)) = (self.lo.to_u64(), self.hi.to_u64()) {
            let exclusive_range: u64 = hi - lo;
            if exclusive_range < u64::MAX {
                Some(exclusive_range + 1)
            } else {
                None
            }
        } else {
            None
        }
    }

    pub fn empty() -> Self {
        Self {
            lo: N::one(),
            hi: N::zero(),
        }
    }

    pub fn is_empty(&self) -> bool {
        self.lo > self.hi
    }

    pub fn new<T: Borrow<N>, U: Borrow<N>>(lo: T, hi: U) -> Self {
        let lo: N = *lo.borrow();
        let hi: N = *hi.borrow();
        Self {
            lo: lo.min(hi),
            hi: hi.max(lo),
        }
    }

    pub unsafe fn new_unchecked<T: Borrow<N>, U: Borrow<N>>(lo: T, hi: U) -> Self {
        let lo: N = *lo.borrow();
        let hi: N = *hi.borrow();
        if lo > hi {
            Self::empty()
        } else {
            Self { lo, hi }
        }
    }

    pub fn union<S: Borrow<Self>>(&self, other: S) -> Self {
        if self.is_empty() {
            *other.borrow()
        } else if other.borrow().is_empty() {
            self.clone()
        } else {
            let other = *other.borrow();
            Self::new(self.lo.min(other.lo), self.hi.max(other.hi))
        }
    }

    pub fn intersect<S: Borrow<Self>>(&self, other: S) -> Self {
        if self.is_empty() || other.borrow().is_empty() {
            Extent::empty()
        } else {
            let other = *other.borrow();
            Self::new(&self.lo.max(other.lo), &self.hi.min(other.hi))
        }
    }

    pub fn contains<T: Borrow<N>>(&self, n: T) -> bool {
        let n = *n.borrow();
        self.lo <= n && n <= self.hi
    }

    pub fn iter(&self) -> ExtentIter<N> {
        ExtentIter(*self)
    }
}

#[derive(Clone, Debug, Default)]
pub struct ExtentIter<N: PrimInt>(Extent<N>);

impl<N: PrimInt> Iterator for ExtentIter<N> {
    type Item = N;

    fn next(&mut self) -> Option<Self::Item> {
        if self.0.is_empty() {
            None
        } else {
            let v = self.0.lo;
            self.0.lo = self.0.lo + N::one();
            Some(v)
        }
    }
}

impl<N: PrimInt> ExtentIter<N> {
    pub fn rev(self) -> ExtentRevIter<N> {
        ExtentRevIter(self.0)
    }
}

pub struct ExtentRevIter<N: PrimInt>(Extent<N>);

impl<N: PrimInt> Iterator for ExtentRevIter<N> {
    type Item = N;

    fn next(&mut self) -> Option<Self::Item> {
        if self.0.is_empty() {
            None
        } else {
            let v = self.0.hi;
            self.0.hi = self.0.hi - N::one();
            Some(v)
        }
    }
}

// std::ops::Range is an exclusive range. Extent is inclusive,
// so we subtract one from any nonempty std::ops::Range.
impl<N: PrimInt> From<Range<N>> for Extent<N> {
    fn from(r: Range<N>) -> Self {
        if r.is_empty() {
            Self::empty()
        } else {
            Self {
                lo: r.start,
                hi: r.end - N::one(),
            }
        }
    }
}

impl<N: PrimInt> TryFrom<Extent<N>> for Range<N> {
    type Error = &'static str;
    fn try_from(e: Extent<N>) -> Result<Self, Self::Error> {
        if e.is_empty() {
            Ok(Range {
                start: N::zero(),
                end: N::zero(),
            })
        } else if e.hi == N::max_value() {
            Err("Extent.hi is N::max_value(), can't represent as Range")
        } else {
            Ok(Range {
                start: e.lo,
                end: e.hi + N::one(),
            })
        }
    }
Examples found in repository?
src/lib.rs (line 177)
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    pub fn union<S: Borrow<Self>>(&self, other: S) -> Self {
        if self.is_empty() {
            *other.borrow()
        } else if other.borrow().is_empty() {
            self.clone()
        } else {
            let other = *other.borrow();
            Self::new(self.lo.min(other.lo), self.hi.max(other.hi))
        }
    }

    pub fn intersect<S: Borrow<Self>>(&self, other: S) -> Self {
        if self.is_empty() || other.borrow().is_empty() {
            Extent::empty()
        } else {
            let other = *other.borrow();
            Self::new(&self.lo.max(other.lo), &self.hi.min(other.hi))
        }
    }

    pub fn contains<T: Borrow<N>>(&self, n: T) -> bool {
        let n = *n.borrow();
        self.lo <= n && n <= self.hi
    }

    pub fn iter(&self) -> ExtentIter<N> {
        ExtentIter(*self)
    }
}

#[derive(Clone, Debug, Default)]
pub struct ExtentIter<N: PrimInt>(Extent<N>);

impl<N: PrimInt> Iterator for ExtentIter<N> {
    type Item = N;

    fn next(&mut self) -> Option<Self::Item> {
        if self.0.is_empty() {
            None
        } else {
            let v = self.0.lo;
            self.0.lo = self.0.lo + N::one();
            Some(v)
        }
    }
}

impl<N: PrimInt> ExtentIter<N> {
    pub fn rev(self) -> ExtentRevIter<N> {
        ExtentRevIter(self.0)
    }
}

pub struct ExtentRevIter<N: PrimInt>(Extent<N>);

impl<N: PrimInt> Iterator for ExtentRevIter<N> {
    type Item = N;

    fn next(&mut self) -> Option<Self::Item> {
        if self.0.is_empty() {
            None
        } else {
            let v = self.0.hi;
            self.0.hi = self.0.hi - N::one();
            Some(v)
        }
    }
}

// std::ops::Range is an exclusive range. Extent is inclusive,
// so we subtract one from any nonempty std::ops::Range.
impl<N: PrimInt> From<Range<N>> for Extent<N> {
    fn from(r: Range<N>) -> Self {
        if r.is_empty() {
            Self::empty()
        } else {
            Self {
                lo: r.start,
                hi: r.end - N::one(),
            }
        }
    }
}

impl<N: PrimInt> TryFrom<Extent<N>> for Range<N> {
    type Error = &'static str;
    fn try_from(e: Extent<N>) -> Result<Self, Self::Error> {
        if e.is_empty() {
            Ok(Range {
                start: N::zero(),
                end: N::zero(),
            })
        } else if e.hi == N::max_value() {
            Err("Extent.hi is N::max_value(), can't represent as Range")
        } else {
            Ok(Range {
                start: e.lo,
                end: e.hi + N::one(),
            })
        }
    }
}

impl<N: PrimInt> From<RangeInclusive<N>> for Extent<N> {
    fn from(r: RangeInclusive<N>) -> Self {
        if r.is_empty() {
            Self::empty()
        } else {
            Self::new(r.start(), r.end())
        }
    }

Trait Implementations§

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Returns the “default value” for a type. Read more
Converts to this type from the input type.
Converts to this type from the input type.
Converts to this type from the input type.
Feeds this value into the given Hasher. Read more
Feeds a slice of this type into the given Hasher. Read more
This method returns an Ordering between self and other. Read more
Compares and returns the maximum of two values. Read more
Compares and returns the minimum of two values. Read more
Restrict a value to a certain interval. Read more
This method tests for self and other values to be equal, and is used by ==. Read more
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more
This method returns an ordering between self and other values if one exists. Read more
This method tests less than (for self and other) and is used by the < operator. Read more
This method tests less than or equal to (for self and other) and is used by the <= operator. Read more
This method tests greater than (for self and other) and is used by the > operator. Read more
This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more
The type returned in the event of a conversion error.
Performs the conversion.

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.