[Home](./index.md) > [kibana-plugin-plugins-expressions-public](./kibana-plugin-plugins-expressions-public.md) > [ExpressionAstExpressionBuilder](./kibana-plugin-plugins-expressions-public.expressionastexpressionbuilder.md) > [findFunction](./kibana-plugin-plugins-expressions-public.expressionastexpressionbuilder.findfunction.md) ## ExpressionAstExpressionBuilder.findFunction property Recursively searches expression for all ocurrences of the function, including in subexpressions. Useful when performing migrations on a specific function, as you can iterate over the array of references and update all functions at once. Signature: ```typescript findFunction: (fnName: InferFunctionDefinition['name']) => Array> | []; ```