remote_data

A type that represents a remote data fetch

Types

RemoteData

pub type RemoteData(a, error) {
  NotAsked
  Loading
  Failure(error)
  Success(a)
}

Constructors

```
NotAsked
```
```
Loading
```
```
Failure(error)
```
```
Success(a)
```

Functions

from_list

</>

pub fn from_list(
  data_list: List(RemoteData(a, b)),
) -> RemoteData(List(a), b)

Convert a list of RemoteData to a RemoteData of a list

Examples

from_list([Success(1), Success(2)])
// -> Success([1, 2])

from_list([Success(1), Failure("error")])
// -> Failure("error")

from_option

</>

pub fn from_option(
  option: Option(a),
  or error: b,
) -> RemoteData(a, b)

Convert an Option to a RemoteData

Examples

from_option(Some(1), or: "error")
// -> Success(1)

from_option(None, or: "error")
// -> Failure("error")

from_result

</>

pub fn from_result(result: Result(a, b)) -> RemoteData(a, b)

Convert a Result to a RemoteData

Examples

from_result(Ok(1))
// -> Success(1)

from_result(Error("error"))
// -> Failure("error")

is_failure

</>

pub fn is_failure(data: RemoteData(a, b)) -> Bool

Check if a RemoteData is a Success

Examples

is_failure(Success(1))
// -> False

is_failure(Failure("error"))
// -> True

is_loading

</>

pub fn is_loading(data: RemoteData(a, b)) -> Bool

Check if a RemoteData is a Success

Examples

is_loading(Success(1))
// -> False

is_loading(Loading)
// -> True

is_not_asked

</>

pub fn is_not_asked(data: RemoteData(a, b)) -> Bool

Check if a RemoteData is a Success

Examples

is_not_asked(Success(1))
// -> False

is_not_asked(NotAsked)
// -> True

is_success

</>

pub fn is_success(data: RemoteData(a, b)) -> Bool

Check if a RemoteData is a Success

Examples

is_success(Success(1))
// -> True

is_success(Failure("error"))
// -> False

map

</>

pub fn map(
  over data: RemoteData(a, b),
  with mapper: fn(a) -> c,
) -> RemoteData(c, b)

Map a function over the success value of a RemoteData

Examples

map(over: Success(1), with: int.to_string)
// -> Success("1")

map(over: Failure("error"), with: int.to_string)
// -> Failure("error")

map2

</>

pub fn map2(
  over data1: RemoteData(a, b),
  over2 data2: RemoteData(c, b),
  with mapper: fn(a, c) -> d,
) -> RemoteData(d, b)

Map a function over the success value of two RemoteData values

Examples

map_2(over: Success(1), over2: Success(2), with: fn(a, b) { a + b })
// -> Success(3)

map_2(over: Failure("error"), over2: Success(2), with: fn(a, b) { a + b })
// -> Failure("error")

map3

</>

pub fn map3(
  over data1: RemoteData(a, b),
  over2 data2: RemoteData(c, b),
  over3 data3: RemoteData(d, b),
  with mapper: fn(a, c, d) -> e,
) -> RemoteData(e, b)

The same as map2, but with three RemoteData values Check map2 for more details

map_error

</>

pub fn map_error(
  over data: RemoteData(a, b),
  with mapper: fn(b) -> c,
) -> RemoteData(a, c)

Map a function over the error value of a RemoteData

Examples

map_error(over: Success(42), with: fn(_) { "error" })
// -> Success(42)

map_error(over: Failure(42), with: fn(_) { "error" })
// -> Failure("error")

to_option

</>

pub fn to_option(data: RemoteData(a, b)) -> Option(a)

Convert a RemoteData to an Option

Examples

to_option(Success(1))
// -> Some(1)

to_option(Failure("error"))
// -> None

to_result

</>

pub fn to_result(
  data: RemoteData(a, b),
  or error: b,
) -> Result(a, b)

Convert a RemoteData to a Result If the data is NotAsked or Loading, it will be converted to an Error with the provided error

Examples

to_result(Success(1), or: "error")
// -> Ok(1)

to_result(Failure("error"), or: "another error")
// -> Error("error")

to_result(Loading, or: "another error")
// -> Error("another error")

try

</>

pub fn try(
  over data: RemoteData(a, b),
  with mapper: fn(a) -> RemoteData(c, b),
) -> RemoteData(c, b)

Chain a function that returns a RemoteData over the success value of a RemoteData

Examples

try(over: Success(1), with: fn(x) { Success(x * 2) })
// -> Success(2)

try(over: Failure("error"), with: fn(x) { Success(x * 2) })
// -> Failure("error")

try(over: Success(1), with: fn(x) { Failure("error") })
// -> Failure("error")

unwrap

</>

pub fn unwrap(data: RemoteData(a, b), or default: a) -> a

Unwrap a RemoteData, providing a default value if the data is not Success

Examples

unwrap(Success(1), or: 0)
// -> 1

unwrap(Failure("error"), or: 0)
// -> 0