Enum DagError 

pub enum DagError {
    Pipeline(PipelineError),
    UnknownReference {
        node: String,
        referenced: String,
    },
    UnmarkedCycle {
        node: String,
    },
    ConflictingBranchFanIn {
        node: String,
        decision: String,
        label_a: String,
        label_b: String,
    },
    SeamMismatch {
        producer: String,
        produced: String,
        consumer: String,
        expected: String,
    },
    Empty,
}

Why a graph was rejected.

Variants

Pipeline(PipelineError)

A per-node signature lookup or seam check failed the same way a linear pipeline’s would.

UnknownReference

A node’s in expression names a node that doesn’t exist.

Fields

node: String

The node whose in expression has the bad reference.

referenced: String

The name it referenced.

UnmarkedCycle

A node has an inbound edge that would form a cycle without an explicit repeat_until marker.

Fields

node: String

The node that could not be ordered.

ConflictingBranchFanIn

A node’s input mixes outputs from two mutually-exclusive branch labels of the same decision.

Fields

node: String

The node whose input mixes two labels.

decision: String

The branching decision both labels belong to.

label_a: String

The first label found.

label_b: String

The second, conflicting label.

SeamMismatch

A node’s declared input doesn’t accept what its in expression produces.

Fields

producer: String

What produced the mismatched value.

produced: String

What it produces.

consumer: String

The node that needed something else.

expected: String

What it needs.

Empty

The graph had no nodes.

Trait Implementations

impl Debug for DagError

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

Formats the value using the given formatter.

impl Display for DagError

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

Formats the value using the given formatter.

impl Error for DagError

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<PipelineError> for DagError

fn from(source: PipelineError) -> Self

Converts to this type from the input type.