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|
//! This crate adds the missing Option::inspect function via an extension trait
//!
/// Extension trait for adding Option::inspect
pub trait OptionInspect<F, T>
where
F: FnOnce(&T),
T: Sized,
{
/// Inspect the Option
///
/// Either call `f` on the value in `Some` or do nothing if this Option is a None.
fn inspect(self, f: F) -> Self;
}
pub trait OptionInspectRef<F, T>
where
F: FnOnce(&T),
T: Sized,
{
fn inspect(&self, f: F);
}
impl<F, T> OptionInspect<F, T> for Option<T>
where
F: FnOnce(&T),
T: Sized,
{
fn inspect(self, f: F) -> Self {
if let Some(o) = self.as_ref() {
(f)(o);
}
self
}
}
impl<F, T> OptionInspectRef<F, T> for Option<T>
where
F: FnOnce(&T),
T: Sized,
{
fn inspect(&self, f: F) {
if let Some(ref o) = self {
(f)(o);
}
}
}
/// Extension trait for adding Option::inspect_none
pub trait OptionInspectNone<F>
where
F: FnOnce(),
{
/// Call `f` if the Option this is called on is a None
fn inspect_none(self, f: F) -> Self;
}
pub trait OptionInspectNoneRef<F>
where
F: FnOnce(),
{
fn inspect_none(&self, f: F);
}
impl<F, T> OptionInspectNone<F> for Option<T>
where
F: FnOnce(),
{
fn inspect_none(self, f: F) -> Self {
if self.is_none() {
(f)();
}
self
}
}
impl<F, T> OptionInspectNoneRef<F> for Option<T>
where
F: FnOnce(),
{
fn inspect_none(&self, f: F) {
if self.is_none() {
(f)();
}
}
}
|
