我有多种功能：
fun testadd(payload) =
({
addition: payload.value1 as Number + payload.value2 as Number
})
fun testsub(payload) =
({
substraction: payload.value1 as Number - payload.value2 as Number
})
fun testmultiply(payload) =
({
multiplication: payload.value1 as Number * payload.value2 as Number
})
我想根据“操作”属性/元素的值动态调用该函数。假设如果“Operation”=“testadd”则调用testadd函数， 如果“Operation”=“testsub”则调用testsub函数
输入 ：
{
"value1" : 10,
"value2" : 20,
"Operation" : "testadd"
}