Struct Range

pub struct Range<T>
where
    T: RangeSubType,
{ /* private fields */ }

A safe deconstruction of a Postgres pg_sys::RangeType struct.

In spirit, Postgres ranges are not dissimilar from Rust ranges, however they are represented quite differently. You’ll use a RangeBound for the lower and upper bounds of a Postgres Range.

Unlike Rust, Postgres also has the concept of an “empty” range. Such ranges are constructed via the Range::empty() function. As such, expect the various direct accessor methods on Range to return Option<&RangeBound<T>> or Option<(RangeBound<T>, RangeBound<T>)>.

pgx provides From implementations for Rust’s built-in range types for easy conversion into a Postgres range. For example:

use pgx::Range;
let r: Range<i32> = (1..10).into();

Implementations

impl<T> Range<T>

where T: RangeSubType,

pub fn new<L, U>(lower: L, upper: U) -> Range<T>

where L: Into<RangeBound<T>>, U: Into<RangeBound<T>>,

Builds a new Range with bounds.

Examples

use pgx::{Range, RangeBound};
let _ = Range::<i32>::new(1, 10);  // `(1..=10)`
let _ = Range::<i32>::new(None, 10); // `(..=10)`
let _ = Range::<i32>::new(1, None); // `(1..)`
let _ = Range::<i32>::new(None, RangeBound::Exclusive(10)); // `(..10)`
let _ = Range::<i32>::new(1, RangeBound::Exclusive(10)); // (`1..10)`
let _ = Range::<i32>::new(None, None); // `(..)`
let _ = Range::<i32>::new(RangeBound::Infinite, RangeBound::Infinite); // `(..)`

pub fn empty() -> Range<T>

Builds an “empty” range

Unlike Rust ranges (from std::ops::), Postgres ranges can be empty, meaning they don’t represent any range of values.

pub fn infinite() -> Range<T>

Builds an “infinite” range. This is equivalent to Rust’s std::ops::RangeFull ((..)).

pub fn lower(&self) -> Option<&RangeBound<T>>

Returns the lower RangeBound

pub fn upper(&self) -> Option<&RangeBound<T>>

Returns the upper RangeBound

pub fn is_empty(&self) -> bool

Returns ‘true’ if the range is “empty”.

pub fn is_infinite(&self) -> bool

Returns true if the range is “infinite”. This is equivalent to Rust’s std::ops::RangeFull ((..))

pub fn into_inner(self) -> Option<(RangeBound<T>, RangeBound<T>)>

Consumes self and returns the internal representation, which can be easily mapped or unwrapped.

A return value of Option::None indicates that this range represents the “empty” range.

pub fn take(&mut self) -> Option<(RangeBound<T>, RangeBound<T>)>

Takes the bounds out of this Range and converts self to represent the “empty” range.

A return value of Option::None indicates that this range already represents the “empty” range.

pub fn replace( &mut self, new: Option<(RangeBound<T>, RangeBound<T>)>, ) -> Option<(RangeBound<T>, RangeBound<T>)>

Replace the bounds of this Range, returning the old bounds.

An Option::None will replace this with the “empty” range.

Methods from Deref<Target = Option<(RangeBound<T>, RangeBound<T>)>>

pub fn is_some(&self) -> bool

Returns true if the option is a Some value.

Examples

let x: Option<u32> = Some(2);
assert_eq!(x.is_some(), true);

let x: Option<u32> = None;
assert_eq!(x.is_some(), false);

pub fn is_none(&self) -> bool

Returns true if the option is a None value.

Examples

let x: Option<u32> = Some(2);
assert_eq!(x.is_none(), false);

let x: Option<u32> = None;
assert_eq!(x.is_none(), true);

pub fn as_ref(&self) -> Option<&T>

Converts from &Option<T> to Option<&T>.

Examples

Calculates the length of an Option<String> as an Option<usize> without moving the String. The map method takes the self argument by value, consuming the original, so this technique uses as_ref to first take an Option to a reference to the value inside the original.

let text: Option<String> = Some("Hello, world!".to_string());
// First, cast `Option<String>` to `Option<&String>` with `as_ref`,
// then consume *that* with `map`, leaving `text` on the stack.
let text_length: Option<usize> = text.as_ref().map(|s| s.len());
println!("still can print text: {text:?}");

pub fn as_mut(&mut self) -> Option<&mut T>

Converts from &mut Option<T> to Option<&mut T>.

Examples

let mut x = Some(2);
match x.as_mut() {
    Some(v) => *v = 42,
    None => {},
}
assert_eq!(x, Some(42));

pub fn as_pin_ref(self: Pin<&Option<T>>) -> Option<Pin<&T>>

Converts from Pin<&Option<T>> to Option<Pin<&T>>.

pub fn as_pin_mut(self: Pin<&mut Option<T>>) -> Option<Pin<&mut T>>

Converts from Pin<&mut Option<T>> to Option<Pin<&mut T>>.

pub fn as_slice(&self) -> &[T]

Returns a slice of the contained value, if any. If this is None, an empty slice is returned. This can be useful to have a single type of iterator over an Option or slice.

Note: Should you have an Option<&T> and wish to get a slice of T, you can unpack it via opt.map_or(&[], std::slice::from_ref).

Examples

assert_eq!(
    [Some(1234).as_slice(), None.as_slice()],
    [&[1234][..], &[][..]],
);

The inverse of this function is (discounting borrowing) [_]::first:

for i in [Some(1234_u16), None] {
    assert_eq!(i.as_ref(), i.as_slice().first());
}

pub fn as_mut_slice(&mut self) -> &mut [T]

Returns a mutable slice of the contained value, if any. If this is None, an empty slice is returned. This can be useful to have a single type of iterator over an Option or slice.

Note: Should you have an Option<&mut T> instead of a &mut Option<T>, which this method takes, you can obtain a mutable slice via opt.map_or(&mut [], std::slice::from_mut).

Examples

assert_eq!(
    [Some(1234).as_mut_slice(), None.as_mut_slice()],
    [&mut [1234][..], &mut [][..]],
);

The result is a mutable slice of zero or one items that points into our original Option:

let mut x = Some(1234);
x.as_mut_slice()[0] += 1;
assert_eq!(x, Some(1235));

The inverse of this method (discounting borrowing) is [_]::first_mut:

assert_eq!(Some(123).as_mut_slice().first_mut(), Some(&mut 123))

pub fn as_deref(&self) -> Option<&<T as Deref>::Target>

where T: Deref,

Converts from Option<T> (or &Option<T>) to Option<&T::Target>.

Leaves the original Option in-place, creating a new one with a reference to the original one, additionally coercing the contents via Deref.

Examples

let x: Option<String> = Some("hey".to_owned());
assert_eq!(x.as_deref(), Some("hey"));

let x: Option<String> = None;
assert_eq!(x.as_deref(), None);

pub fn as_deref_mut(&mut self) -> Option<&mut <T as Deref>::Target>

where T: DerefMut,

Converts from Option<T> (or &mut Option<T>) to Option<&mut T::Target>.

Leaves the original Option in-place, creating a new one containing a mutable reference to the inner type’s Deref::Target type.

Examples

let mut x: Option<String> = Some("hey".to_owned());
assert_eq!(x.as_deref_mut().map(|x| {
    x.make_ascii_uppercase();
    x
}), Some("HEY".to_owned().as_mut_str()));

pub fn iter(&self) -> Iter<'_, T>

Returns an iterator over the possibly contained value.

Examples

let x = Some(4);
assert_eq!(x.iter().next(), Some(&4));

let x: Option<u32> = None;
assert_eq!(x.iter().next(), None);

pub fn iter_mut(&mut self) -> IterMut<'_, T>

Returns a mutable iterator over the possibly contained value.

Examples

let mut x = Some(4);
match x.iter_mut().next() {
    Some(v) => *v = 42,
    None => {},
}
assert_eq!(x, Some(42));

let mut x: Option<u32> = None;
assert_eq!(x.iter_mut().next(), None);

pub fn insert(&mut self, value: T) -> &mut T

Inserts value into the option, then returns a mutable reference to it.

If the option already contains a value, the old value is dropped.

See also Option::get_or_insert, which doesn’t update the value if the option already contains Some.

Example

let mut opt = None;
let val = opt.insert(1);
assert_eq!(*val, 1);
assert_eq!(opt.unwrap(), 1);
let val = opt.insert(2);
assert_eq!(*val, 2);
*val = 3;
assert_eq!(opt.unwrap(), 3);

pub fn get_or_insert(&mut self, value: T) -> &mut T

Inserts value into the option if it is None, then returns a mutable reference to the contained value.

See also Option::insert, which updates the value even if the option already contains Some.

Examples

let mut x = None;

{
    let y: &mut u32 = x.get_or_insert(5);
    assert_eq!(y, &5);

    *y = 7;
}

assert_eq!(x, Some(7));

pub fn get_or_insert_default(&mut self) -> &mut T

where T: Default,

Inserts the default value into the option if it is None, then returns a mutable reference to the contained value.

Examples

let mut x = None;

{
    let y: &mut u32 = x.get_or_insert_default();
    assert_eq!(y, &0);

    *y = 7;
}

assert_eq!(x, Some(7));

pub fn get_or_insert_with<F>(&mut self, f: F) -> &mut T

where F: FnOnce() -> T,

Inserts a value computed from f into the option if it is None, then returns a mutable reference to the contained value.

Examples

let mut x = None;

{
    let y: &mut u32 = x.get_or_insert_with(|| 5);
    assert_eq!(y, &5);

    *y = 7;
}

assert_eq!(x, Some(7));

pub fn take(&mut self) -> Option<T>

Takes the value out of the option, leaving a None in its place.

Examples

let mut x = Some(2);
let y = x.take();
assert_eq!(x, None);
assert_eq!(y, Some(2));

let mut x: Option<u32> = None;
let y = x.take();
assert_eq!(x, None);
assert_eq!(y, None);

pub fn take_if<P>(&mut self, predicate: P) -> Option<T>

where P: FnOnce(&mut T) -> bool,

Takes the value out of the option, but only if the predicate evaluates to true on a mutable reference to the value.

In other words, replaces self with None if the predicate returns true. This method operates similar to Option::take but conditional.

Examples

let mut x = Some(42);

let prev = x.take_if(|v| if *v == 42 {
    *v += 1;
    false
} else {
    false
});
assert_eq!(x, Some(43));
assert_eq!(prev, None);

let prev = x.take_if(|v| *v == 43);
assert_eq!(x, None);
assert_eq!(prev, Some(43));

pub fn replace(&mut self, value: T) -> Option<T>

Replaces the actual value in the option by the value given in parameter, returning the old value if present, leaving a Some in its place without deinitializing either one.

Examples

let mut x = Some(2);
let old = x.replace(5);
assert_eq!(x, Some(5));
assert_eq!(old, Some(2));

let mut x = None;
let old = x.replace(3);
assert_eq!(x, Some(3));
assert_eq!(old, None);

Trait Implementations

impl<T> Clone for Range<T>

where T: Clone + RangeSubType,

fn clone(&self) -> Range<T>

Returns a duplicate of the value.

const fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T> Debug for Range<T>

where T: Debug + RangeSubType,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<T> Deref for Range<T>

where T: RangeSubType,

type Target = Option<(RangeBound<T>, RangeBound<T>)>

The resulting type after dereferencing.

fn deref(&self) -> &<Range<T> as Deref>::Target

Dereferences the value.

impl<T> DerefMut for Range<T>

where T: RangeSubType,

fn deref_mut(&mut self) -> &mut <Range<T> as Deref>::Target

Mutably dereferences the value.

impl<T> Display for Range<T>

where T: RangeSubType + Display,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Follows Postgres’ format for displaying ranges

impl<T> From<Range<T>> for Range<T>

where T: RangeSubType,

fn from(value: Range<T>) -> Range<T>

Converts to this type from the input type.

impl<T> From<RangeFrom<T>> for Range<T>

where T: RangeSubType,

fn from(value: RangeFrom<T>) -> Range<T>

Converts to this type from the input type.

impl<T> From<RangeFull> for Range<T>

where T: RangeSubType,

fn from(_: RangeFull) -> Range<T>

Converts to this type from the input type.

impl<T> From<RangeInclusive<T>> for Range<T>

where T: RangeSubType,

fn from(value: RangeInclusive<T>) -> Range<T>

Converts to this type from the input type.

impl<T> From<RangeTo<T>> for Range<T>

where T: RangeSubType,

fn from(value: RangeTo<T>) -> Range<T>

Converts to this type from the input type.

impl<T> From<RangeToInclusive<T>> for Range<T>

where T: RangeSubType,

fn from(value: RangeToInclusive<T>) -> Range<T>

Converts to this type from the input type.

impl<T> FromDatum for Range<T>

where T: RangeSubType,

unsafe fn from_polymorphic_datum( datum: Datum, is_null: bool, _: Oid, ) -> Option<Range<T>>

where Range<T>: Sized,

Safety

function requires that

• is_null is true OR datum represents a PG RangeType datum

const GET_TYPOID: bool = false

Should a type OID be fetched when calling from_datum?

unsafe fn from_datum(datum: Datum, is_null: bool) -> Option<Self>

where Self: Sized,

Safety

unsafe fn from_datum_in_memory_context( memory_context: PgMemoryContexts, datum: Datum, is_null: bool, typoid: Oid, ) -> Option<Self>

where Self: Sized,

Default implementation switched to the specified memory context and then simply calls FromDatum::from_datum(...) from within that context.

unsafe fn try_from_datum( datum: Datum, is_null: bool, type_oid: Oid, ) -> Result<Option<Self>, TryFromDatumError>

where Self: Sized + IntoDatum,

try_from_datum is a convenience wrapper around FromDatum::from_datum that returns a a Result around an Option, as a Datum can be null. It’s intended to be used in situations where the caller needs to know whether the type conversion succeeded or failed.

unsafe fn try_from_datum_in_memory_context( memory_context: PgMemoryContexts, datum: Datum, is_null: bool, type_oid: Oid, ) -> Result<Option<Self>, TryFromDatumError>

where Self: Sized + IntoDatum,

A version of try_from_datum that switches to the given context to convert from Datum

impl<T> Hash for Range<T>

where T: Hash + RangeSubType,

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T> IntoDatum for Range<T>

where T: RangeSubType,

fn into_datum(self) -> Option<Datum>

fn type_oid() -> Oid

fn composite_type_oid(&self) -> Option<Oid>

fn array_type_oid() -> Oid

fn is_compatible_with(other: Oid) -> bool

Is a Datum of this type compatible with another Postgres type?

impl<T> PartialEq for Range<T>

where T: PartialEq + RangeSubType,

fn eq(&self, other: &Range<T>) -> bool

Tests for self and other values to be equal, and is used by ==.

const fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl SqlTranslatable for Range<AnyNumeric>

fn argument_sql() -> Result<SqlMapping, ArgumentError>

fn return_sql() -> Result<Returns, ReturnsError>

fn type_name() -> &'static str

fn variadic() -> bool

fn optional() -> bool

fn entity() -> FunctionMetadataTypeEntity

impl SqlTranslatable for Range<Date>

fn argument_sql() -> Result<SqlMapping, ArgumentError>

fn return_sql() -> Result<Returns, ReturnsError>

fn type_name() -> &'static str

fn variadic() -> bool

fn optional() -> bool

fn entity() -> FunctionMetadataTypeEntity

impl<const P: u32, const S: u32> SqlTranslatable for Range<Numeric<P, S>>

fn argument_sql() -> Result<SqlMapping, ArgumentError>

fn return_sql() -> Result<Returns, ReturnsError>

fn type_name() -> &'static str

fn variadic() -> bool

fn optional() -> bool

fn entity() -> FunctionMetadataTypeEntity

impl SqlTranslatable for Range<Timestamp>

fn argument_sql() -> Result<SqlMapping, ArgumentError>

fn return_sql() -> Result<Returns, ReturnsError>

fn type_name() -> &'static str

fn variadic() -> bool

fn optional() -> bool

fn entity() -> FunctionMetadataTypeEntity

impl SqlTranslatable for Range<TimestampWithTimeZone>

fn argument_sql() -> Result<SqlMapping, ArgumentError>

fn return_sql() -> Result<Returns, ReturnsError>

fn type_name() -> &'static str

fn variadic() -> bool

fn optional() -> bool

fn entity() -> FunctionMetadataTypeEntity

impl SqlTranslatable for Range<i32>

fn argument_sql() -> Result<SqlMapping, ArgumentError>

fn return_sql() -> Result<Returns, ReturnsError>

fn type_name() -> &'static str

fn variadic() -> bool

fn optional() -> bool

fn entity() -> FunctionMetadataTypeEntity

impl SqlTranslatable for Range<i64>

fn argument_sql() -> Result<SqlMapping, ArgumentError>

fn return_sql() -> Result<Returns, ReturnsError>

fn type_name() -> &'static str

fn variadic() -> bool

fn optional() -> bool

fn entity() -> FunctionMetadataTypeEntity

impl<T> Eq for Range<T>

where T: Eq + RangeSubType,

impl<T> StructuralPartialEq for Range<T>

where T: RangeSubType,