I'm working with Javascript to build a mapping function, that, given a scheme should find the mapper's object's value within an application variable.
My attempt at doing this results in an undefined error and I'm trying to figure out what I need to change to make it work correctly, I've put together a JS fiddle that can be found here as well.
const application = {
state: {
outgoings: {
credit: 0,
food: 0
}
}
}
const mapper = {
"AppFoodSpend": "outgoings.food",
"AppCreditSpend": "outgoings.credit"
}
for (const field in mapper) {
console.log(application.state[mapper[field]])
// expected results should be credit 0 and food 0
}
For further context, I have an object called application which contains some fields, they may not always be in the same order. My mapper object contains some key/value pairs, and it's the value that I'd like to try and find in application. for for instance, my console log should be retrieving something like:
application.state.outgoings.foodapplication.state.outgoings.creditThey may not always be in this order, so I need to (on each iteration of the mapper) find the key in my application variable.
What do I need to change here?
Strings like 'outgoings.food' are not valid to navigate a data structure. You could use some "lenses" lib or write something like this...
const mapper = {
"AppFoodSpend": ["outgoings", "food"],
"AppCreditSpend": ["outgoings", "credit"]
}
for (const field in mapper) {
console.log(
mapper[field].reduce(
(ctx, path) => ctx[path],
application.state
)
)
}