Enum ValidationError 

#[non_exhaustive]
pub enum ValidationError {
    NoEntryPoint,
    InvalidEntryPoint(NodeId),
    InvalidEdgeSource {
        edge: EdgeId,
        node: NodeId,
    },
    InvalidEdgeTarget {
        edge: EdgeId,
        node: NodeId,
    },
    MissingPredicate {
        node: NodeId,
        name: &'static str,
    },
    MissingBranch {
        node: NodeId,
        name: &'static str,
        branch: &'static str,
    },
    InvalidBranchTarget {
        node: NodeId,
        branch: &'static str,
        target: NodeId,
    },
    MissingDiscriminator {
        node: NodeId,
        name: &'static str,
    },
    EmptySwitch {
        node: NodeId,
        name: &'static str,
    },
    InvalidCaseTarget {
        node: NodeId,
        case: &'static str,
        target: NodeId,
    },
    InvalidDefaultTarget {
        node: NodeId,
        target: NodeId,
    },
    EmptyParallel {
        node: NodeId,
        name: &'static str,
    },
    NoTerminationCondition {
        node: NodeId,
        name: &'static str,
    },
    EmptyLoopBody {
        node: NodeId,
        name: &'static str,
    },
    InvalidLoopBody {
        node: NodeId,
        target: NodeId,
    },
    LoopPredicateOutputNotProduced {
        node: NodeId,
        name: &'static str,
        expected_output: &'static str,
    },
    MissingEdgeRequirement {
        node: NodeId,
        name: &'static str,
        requirement: &'static str,
    },
    EmptyScopeGraph {
        node: NodeId,
        name: &'static str,
    },
    ScopeGraphNoEntryPoint {
        node: NodeId,
        name: &'static str,
    },
    ScopeGraphInvalid {
        node: NodeId,
        name: &'static str,
        inner: Box<ValidationError>,
    },
}

Errors that can occur during graph validation.

These errors are detected at build time (when calling Graph::validate) before the graph is executed, allowing early detection of structural issues.

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.

NoEntryPoint

The graph has no entry point.

InvalidEntryPoint(NodeId)

The entry point references an invalid node.

InvalidEdgeSource

An edge’s source node doesn’t exist.

Fields

edge: EdgeId

The edge ID.

node: NodeId

The invalid node ID.

InvalidEdgeTarget

An edge’s target node doesn’t exist.

Fields

edge: EdgeId

The edge ID.

node: NodeId

The invalid node ID.

MissingPredicate

A decision node is missing its predicate.

Fields

node: NodeId

The node ID.

name: &'static str

The node name.

MissingBranch

A decision node is missing a branch target.

Fields

node: NodeId

The node ID.

name: &'static str

The node name.

branch: &'static str

Which branch is missing (“true” or “false”).

InvalidBranchTarget

A branch target references an invalid node.

Fields

node: NodeId

The node ID.

branch: &'static str

The branch name.

target: NodeId

The invalid target node ID.

MissingDiscriminator

A switch node is missing its discriminator.

Fields

node: NodeId

The node ID.

name: &'static str

The node name.

EmptySwitch

A switch node has no cases and no default.

Fields

node: NodeId

The node ID.

name: &'static str

The node name.

InvalidCaseTarget

A switch case target references an invalid node.

Fields

node: NodeId

The node ID.

case: &'static str

The case name.

target: NodeId

The invalid target node ID.

InvalidDefaultTarget

A switch default target references an invalid node.

Fields

node: NodeId

The node ID.

target: NodeId

The invalid target node ID.

EmptyParallel

A parallel node has no branches.

Fields

node: NodeId

The node ID.

name: &'static str

The node name.

NoTerminationCondition

A loop node has no termination condition.

Fields

node: NodeId

The node ID.

name: &'static str

The node name.

EmptyLoopBody

A loop node has no body.

Fields

node: NodeId

The node ID.

name: &'static str

The node name.

InvalidLoopBody

A loop body entry references an invalid node.

Fields

node: NodeId

The node ID.

target: NodeId

The invalid target node ID.

LoopPredicateOutputNotProduced

A loop’s termination predicate reads an output type that no system in the loop body produces.

Fields

node: NodeId

The loop node ID.

name: &'static str

The loop node name.

expected_output: &'static str

The output type the predicate expects.

MissingEdgeRequirement

A system requires a specific edge type but is not reachable via that edge.

For example, a system using CaughtError must be the target of an error edge; placing it on a normal sequential path is a wiring mistake.

Fields

node: NodeId

The node ID.

name: &'static str

The system name.

requirement: &'static str

A human-readable description of the required edge type.

EmptyScopeGraph

A scope node contains an empty graph.

Fields

node: NodeId

The scope node ID.

name: &'static str

The scope node name.

ScopeGraphNoEntryPoint

A scope node’s embedded graph has no entry point.

Fields

node: NodeId

The scope node ID.

name: &'static str

The scope node name.

ScopeGraphInvalid

A scope node’s embedded graph has a validation error.

Fields

node: NodeId

The scope node ID.

name: &'static str

The scope node name.

inner: Box<ValidationError>

The inner validation error from the embedded graph.

Trait Implementations

impl Clone for ValidationError

fn clone(&self) -> ValidationError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ValidationError

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

Formats the value using the given formatter.

impl Display for ValidationError

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

Formats the value using the given formatter.

impl Error for ValidationError

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.