Enum shortcut::cmp::Value

pub enum Value<'a, T: Clone + 'a> {
    Const(Cow<'a, T>),
    Column(usize),
}

A value represents something to compare against.

Variants

Const(Cow<'a, T>)

A constant value literal.

Column(usize)

A different column for the same row. Note that comparisons of this kind cannot use an index, at least not in the current implementation.

Implementations

impl<'a, T: Clone + 'a> Value<'a, T>

pub fn value<'b: 'a, R: Row<T> + ?Sized>(&'b self, row: &'b R) -> &'b T

Extract the value literal for this Value when evaluated for the given row. For Const values, this evaluates to the Const value itself. For Column, it evaluates to the value of that column in the given row.

pub fn new<I: Into<T>>(t: I) -> Self

Construct a new Value by moving an existing value.

pub fn using<I: Borrow<T>>(t: &'a I) -> Self

Construct a new Value by using a reference to an existing value.

pub fn column(c: usize) -> Self

Construct a new Value that refers to the value in a particular column of a row.

Trait Implementations

impl<'a, T: Clone + Clone + 'a> Clone for Value<'a, T>

fn clone(&self) -> Value<'a, T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'a, T: Debug + Clone + 'a> Debug for Value<'a, T>

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

Formats the value using the given formatter.

impl<'a, T: Display + Clone + 'a> Display for Value<'a, T>

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

Formats the value using the given formatter.