Struct NoCustomData 

pub struct NoCustomData;

Stands in for a customData object this deployment doesn’t read.

2.0.1 and 2.1 hang an optional customData field on nearly every object in the specification – 151 structs in 2.1 alone – for vendor extensions. Storing the spec’s shape inline costs 264 bytes at every one of those nodes, and because structs nest by value that cost is multiplied by the whole type graph rather than paid once.

So the field’s type is a parameter, and this is its default: a zero-sized type, making Option<NoCustomData> one byte.

It is deliberately permissive, not empty. A peer may send customData whenever it likes, so the default has to accept and discard it – Option<()> would only accept null and would fail to parse any message that actually carried an extension. That would turn opting out of custom data into an interop bug.

The trade is that discarded data is not echoed back: re-serializing a value parsed into NoCustomData writes {}, not what arrived. A deployment that needs the contents names its own type instead:

use ocpp_types::v21::common::{Component, CustomData};

// The specification's own shape, opted into:
let with_spec_shape: Component<CustomData> = Component {
    custom_data: None,
    evse: None,
    instance: None,
    name: heapless::String::try_from("EVSE").unwrap(),
};

Trait Implementations

impl Clone for NoCustomData

fn clone(&self) -> NoCustomData

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for NoCustomData

impl Debug for NoCustomData

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

Formats the value using the given formatter.

impl Default for NoCustomData

fn default() -> NoCustomData

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for NoCustomData

Available on crate feature serde only.

fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error>

Deserialize this value from the given Serde deserializer.

impl Eq for NoCustomData

impl Hash for NoCustomData

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for NoCustomData

fn cmp(&self, other: &NoCustomData) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for NoCustomData

fn eq(&self, other: &NoCustomData) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for NoCustomData

fn partial_cmp(&self, other: &NoCustomData) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for NoCustomData

Available on crate feature serde only.

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for NoCustomData