Trait diesel::prelude::OptionalEmptyChangesetExtension

pub trait OptionalEmptyChangesetExtension<T> {
    // Required method
    fn optional_empty_changeset(self) -> Result<Option<T>, Error>;
}

See the method documentation.

Required Methods

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

By default, Diesel treats an empty update as a QueryBuilderError. This method will convert that error into None.

Example

use diesel::{QueryResult, OptionalEmptyChangesetExtension, result::Error::QueryBuilderError, result::EmptyChangeset};
let result: QueryResult<i32> = Err(QueryBuilderError(Box::new(EmptyChangeset)));
assert_eq!(Ok(None), result.optional_empty_changeset());

Implementors

impl<T> OptionalEmptyChangesetExtension<T> for QueryResult<T>