Struct rug::integer::MiniInteger

pub struct MiniInteger { /* private fields */ }

A small integer that does not require any memory allocation.

This can be useful when you have a primitive integer type such as u64 or i8, but need a reference to an Integer.

If there are functions that take a u32 or i32 directly instead of an Integer reference, using them can still be faster than using a MiniInteger; the functions would still need to check for the size of an Integer obtained using MiniInteger.

The borrow method returns an object that can be coerced to an Integer, as it implements Deref<Target = Integer>.

Examples

use rug::integer::MiniInteger;
use rug::Integer;
// `a` requires a heap allocation
let mut a = Integer::from(250);
// `b` can reside on the stack
let b = MiniInteger::from(-100);
a.lcm_mut(&b.borrow());
assert_eq!(a, 500);
// another computation:
a.lcm_mut(&MiniInteger::from(30).borrow());
assert_eq!(a, 1500);

Implementations

impl MiniInteger

pub const fn new() -> Self

Creates a MiniInteger with value 0.

Examples

use rug::integer::MiniInteger;
let i = MiniInteger::new();
// Borrow i as if it were Integer.
assert_eq!(*i.borrow(), 0);

pub unsafe fn as_nonreallocating_integer(&mut self) -> &mut Integer

Returns a mutable reference to an Integer for simple operations that do not need to allocate more space for the number.

Safety

It is undefined behavior to perform operations that reallocate the internal data of the referenced Integer or to swap it with another number.

Some GMP functions swap the allocations of their target operands; calling such functions with the mutable reference returned by this method can lead to undefined behavior.

Examples

use rug::integer::MiniInteger;
use rug::Assign;
let mut i = MiniInteger::from(1u64);
let capacity = i.borrow().capacity();
// another u64 will not require a reallocation
unsafe {
    i.as_nonreallocating_integer().assign(2u64);
}
assert_eq!(*i.borrow(), 2);
assert_eq!(i.borrow().capacity(), capacity);

pub fn borrow(&self) -> impl Deref<Target = Integer> + '_

Borrows the integer.

The returned object implements Deref<Target = Integer>.

The borrow lasts until the returned object exits scope. Multiple borrows can be taken at the same time.

Examples

use rug::integer::MiniInteger;
use rug::Integer;
let i = MiniInteger::from(-13i32);
let b = i.borrow();
let abs_ref = b.abs_ref();
assert_eq!(Integer::from(abs_ref), 13);

pub fn borrow_excl(&mut self) -> &Integer

Borrows the integer exclusively.

This is similar to the borrow method, but it requires exclusive access to the underlying MiniInteger; the returned reference can however be shared. The exclusive access is required to reduce the amount of housekeeping necessary, providing a more efficient operation.

Examples

use rug::integer::MiniInteger;
use rug::Integer;
let mut i = MiniInteger::from(-13i32);
let b = i.borrow_excl();
let abs_ref = b.abs_ref();
assert_eq!(Integer::from(abs_ref), 13);

Trait Implementations

impl Assign<&MiniInteger> for Integer

fn assign(&mut self, src: &MiniInteger)

Peforms the assignement.

impl Assign<&MiniInteger> for MiniInteger

fn assign(&mut self, other: &Self)

Peforms the assignement.

impl Assign<MiniInteger> for Integer

fn assign(&mut self, src: MiniInteger)

Peforms the assignement.

impl<T: ToMini> Assign<T> for MiniInteger

fn assign(&mut self, src: T)

Peforms the assignement.

impl Assign for MiniInteger

fn assign(&mut self, other: Self)

Peforms the assignement.

impl Binary for MiniInteger

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

Formats the value using the given formatter.

impl Clone for MiniInteger

fn clone(&self) -> MiniInteger

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for MiniInteger

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

Formats the value using the given formatter.

impl Default for MiniInteger

fn default() -> Self

Returns the “default value” for a type.

impl Display for MiniInteger

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

Formats the value using the given formatter.

impl From<&MiniInteger> for Integer

fn from(src: &MiniInteger) -> Self

Converts to this type from the input type.

impl From<MiniInteger> for Integer

fn from(src: MiniInteger) -> Self

Converts to this type from the input type.

impl<T: ToMini> From<T> for MiniInteger

fn from(src: T) -> Self

Converts to this type from the input type.

impl LowerHex for MiniInteger

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

Formats the value using the given formatter.

impl Octal for MiniInteger

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

Formats the value using the given formatter.

impl PartialEq<Integer> for MiniInteger

fn eq(&self, other: &Integer) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

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

impl PartialEq<MiniInteger> for Integer

fn eq(&self, other: &MiniInteger) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

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

impl PartialOrd<Integer> for MiniInteger

fn partial_cmp(&self, other: &Integer) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

This method tests less than (for self and other) and is used by the < operator.

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

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

This method tests greater than (for self and other) and is used by the > operator.

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl PartialOrd<MiniInteger> for Integer

fn partial_cmp(&self, other: &MiniInteger) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

This method tests less than (for self and other) and is used by the < operator.

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

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

This method tests greater than (for self and other) and is used by the > operator.

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl UpperHex for MiniInteger

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

Formats the value using the given formatter.

impl Copy for MiniInteger

impl Send for MiniInteger

impl Sync for MiniInteger