Struct MergeCell

pub struct MergeCell<T> { /* private fields */ }

A memory location that allows repeated merging.

This type acts like an “accumulator” for merging. It allows merging many values and defering merge errors for later.

MergeCell deliberately does not implement Merge. It is not intended to be merged with other values, rather it expects to have values merged into it.

Example

let mut cell = MergeCell::empty();

cell.merge(vec![1, 2]);
cell.merge(vec![]);
cell.merge(vec![0, 4, 8]);

let merged = cell.try_finish().unwrap().unwrap();
assert_eq!(merged, &[1, 2, 0, 4, 8]);

Implementations

impl<T> MergeCell<T>

pub fn empty() -> Self

Create a new empty MergeCell.

pub fn new(value: T) -> Self

Create a new MergeCell that is initialized with value.

pub fn is_empty(&self) -> bool

Check whether the cell is empty.

The cell is empty if and only if it was created with empty() and no values have been merge()d.

pub fn has_errored(&self) -> bool

Check whether a previous merge() operation has failed.

pub fn finish(self) -> Result<T, Error>

Destruct the MergeCell and get back the final merged value.

Returns the result of all of the merge() operations on the cell.

Panics

If the MergeCell is empty. For the non-panicking version of this method, see: try_finish().

Example

let mut cell = MergeCell::empty();

cell.merge(vec![1, 2]);
cell.merge(vec![]);
cell.merge(vec![0, 4, 8]);

let merged = cell.finish().unwrap();
assert_eq!(merged, &[1, 2, 0, 4, 8]);

pub fn try_finish(self) -> Option<Result<T, Error>>

Destruct the MergeCell and get back the final merged value.

This is the non-panicking version of finish().

Returns None if the cell is empty. Otherwise, it is functionally the same as finish().

Example

let mut cell = MergeCell::empty();

cell.merge(vec![1, 2]);
cell.merge(vec![]);
cell.merge(vec![0, 4, 8]);

let merged = cell.try_finish().unwrap().unwrap();
assert_eq!(merged, &[1, 2, 0, 4, 8]);

impl<T> MergeCell<T>

where T: Merge,

pub fn merge(&mut self, other: T)

Merge other into the cell.

This function will fill the cell if it is empty.

Trait Implementations

impl<T: Debug> Debug for MergeCell<T>

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

Formats the value using the given formatter.

impl<T> Default for MergeCell<T>

fn default() -> Self

Returns the “default value” for a type.