Enum LayoutError 

#[non_exhaustive]
pub enum LayoutError {
    Unresolved {
        node: NodeId,
    },
    UnsupportedForEncoding {
        node: NodeId,
        encoding: Encoding,
        reason: &'static str,
    },
    KeyMustBeBigEndian,
    TooDeep {
        node: NodeId,
    },
    RecursionOutsideCollection {
        node: NodeId,
    },
    Model(AstError),
}

Why a layout could not be computed.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Unresolved

A reference in the type graph is not resolved, so the size and alignment behind it are unknown. Guessing would produce a plan that is wrong on the wire, which is worse than no plan.

Fields

node: NodeId

The type whose reference could not be followed.

UnsupportedForEncoding

The construct has no representation in the requested encoding.

Fields

node: NodeId

The offending type.

encoding: Encoding

The encoding asked for.

reason: &'static str

Why it does not fit.

KeyMustBeBigEndian

A key-holder plan was asked for in little-endian. The key holder is defined big-endian; honouring the request would produce a wrong hash. DDSI-RTPS 2.5 §9.6.3.8.

TooDeep

The type graph nests deeper than the planner will follow.

Fields

node: NodeId

Where the descent stopped.

RecursionOutsideCollection

A member’s type closes a cycle with nothing on it that can terminate a value.

IDL 4.2 §7.4.1.4.4.4.4 admits a recursive structure or union “via members that have a sequence type” — “an incomplete type can only appear as the element type of a sequence definition” — because the element count is what makes a value finite. A map carries a count the same way, and an @optional member carries the same property in the other form: the member can be absent, and an absent member ends the value where a zero-length sequence would. A cycle over any of the three is planned; a cycle over none of them has no finite value at all and is refused here, by name rather than by a depth limit that would report a number and not a reason. An array is the case that fails it: its element count is fixed and non-zero, so nothing about a value can stop the descent.

XTypes 1.3 §7.3.1.2.1.4 is not a second ground for this refusal. It refuses a cyclic value — “if the graph of objects has cycles, it is not serializable” — and a recursive type whose values are trees has none. That distinction is a value-time question and is answered at value time; see zerodds_wire_codec::MAX_VALUE_DEPTH.

Fields

node: NodeId

The member whose type names an enclosing type.

Model(AstError)

The model rejected a lookup.

Trait Implementations

impl Clone for LayoutError

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LayoutError

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

Formats the value using the given formatter.

impl Display for LayoutError

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

Formats the value using the given formatter.

impl Eq for LayoutError

impl Error for LayoutError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl From<AstError> for LayoutError

fn from(error: AstError) -> Self

Converts to this type from the input type.

impl PartialEq for LayoutError

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for LayoutError