Struct hateoas::Content

source ·
pub struct Content<T> { /* private fields */ }

Implementations§

Setting the content on the Content container

use hateoas::Content;
let mut ctn_with_content = Content::new(());

assert_eq!(ctn_with_content.has_content(), true);
assert_eq!(ctn_with_content.content(), &Some(()));
Examples found in repository?
src/content.rs (line 147)
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    fn from(t: T) -> Self {
        Content::new(t)
    }

Checking if the content has any information in it, eg. is not none

use hateoas::Content;
let ctn: Content<()> = Content::default();
let mut ctn_with_content = Content::new(Some(()));

assert_eq!(ctn.has_content(), false);
assert_eq!(ctn_with_content.has_content(), true);

Getting a mut reference of the current spec content This will get a Option<&mut T> of the current contents spec piece. This will allow for modification of the internal content in the spec

use hateoas::{Content};
let mut ctn: Content<String> = Content::default();

assert_eq!(ctn.content_mut(), &None);

let mut_ctn = ctn.content_mut();
*(mut_ctn) = Some("bar".to_string());

assert_eq!(ctn.content(), &Some("bar".to_string()));

Getting a reference of the current spec content This will get a Option of the current contents spec piece

use hateoas::{Content, RelLinkCollection};
let mut ctn = Content::default();

assert_eq!(ctn.content(), &None);

*(ctn.content_mut()) = Some(());

assert_eq!(ctn.content(), &Some(()))

Get the rel even if not set.

use hateoas::{Content, RelLinkCollection};

let mut content: Content<()> = Content::default();
let rel = content.rel();

assert_eq!(rel, &mut RelLinkCollection::default())

Methods from Deref<Target = Option<T>>§

Returns true if the option is a Some value.

Examples
let x: Option<u32> = Some(2);
assert_eq!(x.is_some(), true);

let x: Option<u32> = None;
assert_eq!(x.is_some(), false);

Returns true if the option is a None value.

Examples
let x: Option<u32> = Some(2);
assert_eq!(x.is_none(), false);

let x: Option<u32> = None;
assert_eq!(x.is_none(), true);

Converts from &Option<T> to Option<&T>.

Examples

Converts an Option<String> into an Option<usize>, preserving the original. The map method takes the self argument by value, consuming the original, so this technique uses as_ref to first take an Option to a reference to the value inside the original.

let text: Option<String> = Some("Hello, world!".to_string());
// First, cast `Option<String>` to `Option<&String>` with `as_ref`,
// then consume *that* with `map`, leaving `text` on the stack.
let text_length: Option<usize> = text.as_ref().map(|s| s.len());
println!("still can print text: {text:?}");

Converts from &mut Option<T> to Option<&mut T>.

Examples
let mut x = Some(2);
match x.as_mut() {
    Some(v) => *v = 42,
    None => {},
}
assert_eq!(x, Some(42));

Converts from Pin<&Option<T>> to Option<Pin<&T>>.

Converts from Pin<&mut Option<T>> to Option<Pin<&mut T>>.

Converts from Option<T> (or &Option<T>) to Option<&T::Target>.

Leaves the original Option in-place, creating a new one with a reference to the original one, additionally coercing the contents via Deref.

Examples
let x: Option<String> = Some("hey".to_owned());
assert_eq!(x.as_deref(), Some("hey"));

let x: Option<String> = None;
assert_eq!(x.as_deref(), None);

Converts from Option<T> (or &mut Option<T>) to Option<&mut T::Target>.

Leaves the original Option in-place, creating a new one containing a mutable reference to the inner type’s Deref::Target type.

Examples
let mut x: Option<String> = Some("hey".to_owned());
assert_eq!(x.as_deref_mut().map(|x| {
    x.make_ascii_uppercase();
    x
}), Some("HEY".to_owned().as_mut_str()));

Returns an iterator over the possibly contained value.

Examples
let x = Some(4);
assert_eq!(x.iter().next(), Some(&4));

let x: Option<u32> = None;
assert_eq!(x.iter().next(), None);

Returns a mutable iterator over the possibly contained value.

Examples
let mut x = Some(4);
match x.iter_mut().next() {
    Some(v) => *v = 42,
    None => {},
}
assert_eq!(x, Some(42));

let mut x: Option<u32> = None;
assert_eq!(x.iter_mut().next(), None);

Inserts value into the option, then returns a mutable reference to it.

If the option already contains a value, the old value is dropped.

See also Option::get_or_insert, which doesn’t update the value if the option already contains Some.

Example
let mut opt = None;
let val = opt.insert(1);
assert_eq!(*val, 1);
assert_eq!(opt.unwrap(), 1);
let val = opt.insert(2);
assert_eq!(*val, 2);
*val = 3;
assert_eq!(opt.unwrap(), 3);

Inserts value into the option if it is None, then returns a mutable reference to the contained value.

See also Option::insert, which updates the value even if the option already contains Some.

Examples
let mut x = None;

{
    let y: &mut u32 = x.get_or_insert(5);
    assert_eq!(y, &5);

    *y = 7;
}

assert_eq!(x, Some(7));
🔬This is a nightly-only experimental API. (option_get_or_insert_default)

Inserts the default value into the option if it is None, then returns a mutable reference to the contained value.

Examples
#![feature(option_get_or_insert_default)]

let mut x = None;

{
    let y: &mut u32 = x.get_or_insert_default();
    assert_eq!(y, &0);

    *y = 7;
}

assert_eq!(x, Some(7));

Inserts a value computed from f into the option if it is None, then returns a mutable reference to the contained value.

Examples
let mut x = None;

{
    let y: &mut u32 = x.get_or_insert_with(|| 5);
    assert_eq!(y, &5);

    *y = 7;
}

assert_eq!(x, Some(7));

Takes the value out of the option, leaving a None in its place.

Examples
let mut x = Some(2);
let y = x.take();
assert_eq!(x, None);
assert_eq!(y, Some(2));

let mut x: Option<u32> = None;
let y = x.take();
assert_eq!(x, None);
assert_eq!(y, None);

Replaces the actual value in the option by the value given in parameter, returning the old value if present, leaving a Some in its place without deinitializing either one.

Examples
let mut x = Some(2);
let old = x.replace(5);
assert_eq!(x, Some(5));
assert_eq!(old, Some(2));

let mut x = None;
let old = x.replace(3);
assert_eq!(x, Some(3));
assert_eq!(old, None);
🔬This is a nightly-only experimental API. (option_result_contains)

Returns true if the option is a Some value containing the given value.

Examples
#![feature(option_result_contains)]

let x: Option<u32> = Some(2);
assert_eq!(x.contains(&2), true);

let x: Option<u32> = Some(3);
assert_eq!(x.contains(&2), false);

let x: Option<u32> = None;
assert_eq!(x.contains(&2), false);

Trait Implementations§

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Returns the “default value” for a type. Read more

Dereferencing the Internal [T] from the Content object This allows us to better operate on the content itself and use it without having to extract it.

use std::ops::Deref;
use hateoas::Content;
let content: Content<()> = Content::default();
let content_opt: &Option<()> = content.deref();

assert_eq!(content_opt, &None);
The resulting type after dereferencing.

Dereferencing the Internal [T] from the Content object This allows us to better operate on the content itself and use it without having to extract it.

use std::ops::{Deref, DerefMut};
use hateoas::Content;
let mut content: Content<()> = Content::default();
let content_opt: &Option<()> = content.deref_mut();

assert_eq!(content_opt, &mut None);
Deserialize this value from the given Serde deserializer. Read more
Convert from any type into a content type.

This will simply wrap the T in a Content allowing for easier manipulation.

use hateoas::Content;
let void: Content<()> = ().into();

assert_eq!(void, Content::new(()));
This method tests for self and other values to be equal, and is used by ==.
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
Serialize this value into the given Serde serializer. Read more

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more
Converts to this type from the input type.

Returns the argument unchanged.

Converts to this type from a reference to the input type.
Instruments this type with the provided Span, returning an Instrumented wrapper. Read more
Instruments this type with the current Span, returning an Instrumented wrapper. Read more

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Should always be Self
The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.
Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more
Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more