[Home](./index.md) > [kibana-plugin-plugins-expressions-public](./kibana-plugin-plugins-expressions-public.md) > [ExpressionRenderDefinition](./kibana-plugin-plugins-expressions-public.expressionrenderdefinition.md) > [validate](./kibana-plugin-plugins-expressions-public.expressionrenderdefinition.validate.md) ## ExpressionRenderDefinition.validate property Used to validate the data before calling the render function. Signature: ```typescript validate?: () => undefined | Error; ```