Trait ColumnValue 

pub trait ColumnValue: Copy + PartialEq {
    const IS_INTEGER: bool;

    // Required methods
    fn to_bits(self) -> u64;
    fn from_bits(bits: u64) -> Option<Self>;
}

A value that can live in an encoded column.

Encodings work on the bit pattern, so anything with a lossless 64-bit representation qualifies. Bit-packing a float is legal and never chosen: the encoder’s rules only reach for it where the values are small integers.

Required Associated Constants

const IS_INTEGER: bool

Whether the bit pattern is an integer, so that narrowing it or taking differences between successive values means something.

False for floating point. Bit-packing a float would sometimes succeed — small floats have leading zero bits — and would produce a column whose size depended on the exponents in it, which is not an encoding anyone chose.

Required Methods

fn to_bits(self) -> u64

The value as bits.

fn from_bits(bits: u64) -> Option<Self>

The value from bits.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl ColumnValue for f32

const IS_INTEGER: bool = false

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

impl ColumnValue for i8

const IS_INTEGER: bool = true

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

impl ColumnValue for i16

const IS_INTEGER: bool = true

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

impl ColumnValue for i32

const IS_INTEGER: bool = true

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

impl ColumnValue for i64

const IS_INTEGER: bool = true

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

impl ColumnValue for u8

const IS_INTEGER: bool = true

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

impl ColumnValue for u16

const IS_INTEGER: bool = true

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

impl ColumnValue for u32

const IS_INTEGER: bool = true

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

impl ColumnValue for u64

const IS_INTEGER: bool = true

fn to_bits(self) -> u64

fn from_bits(bits: u64) -> Option<Self>

Implementors

impl ColumnValue for SymbolId

const IS_INTEGER: bool = true