# Class ExpressionsInvoker

OptimaJet.Workflow.Core.CodeActions.ExpressionsInvoker

Evaluates the combined [ConditionType.Expression](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.Model/ConditionType/) conditions registered for process transitions.

Namespace: [OptimaJet.Workflow.Core.CodeActions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.CodeActions/)

```csharp
public sealed class ExpressionsInvoker : FunctionInvoker<bool>
```

## Type Hierarchy

-   [FunctionInvoker<bool>](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.CodeActions/FunctionInvoker-TReturn/)
    -   ExpressionsInvoker Current type

## Properties

`protected override FunctionInvoker<bool>.InvokerNotFoundReactionType InvokerNotFoundReaction { get; }` 

Gets the behavior applied by the [FunctionInvoker<TReturn>.InvokeAsync(TransitionDefinition, ProcessInstance)](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.CodeActions/FunctionInvoker-TReturn/) methods when no function is registered for the requested transition.

`public override string FunctionName { get; }` 

Gets the label included in compilation-error and missing-function messages.

`public static string FunctionNameStatic { get; }` 

Gets the diagnostic label for expression-condition functions.

## Remarks

Requesting a transition for which no expression function is registered throws an exception.

[Previous ExpressionsCompilerOptions](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.CodeActions/ExpressionsCompilerOptions/) [Next ExpressionsUtils](https://api.workflowengine.io/core/OptimaJet.Workflow.Core.CodeActions/ExpressionsUtils/)