I'm trying to create a map normalized by object's key from an array of objects using reduce. The array is defined using a const assertion - as const
:
const flavors = [
{ type: 'sweet' },
{ type: 'sour' },
] as const;
The desired normalized map looks like this:
const expectedFlavorsMap = {
'sweet': { type: 'sweet' },
'sour': { type: 'sour' }
} as const;
Now to create such map, I am using a reduce function so that keys are type
and values are the objects itself from the flavors
array.
const flavorsMap = flavors.reduce((acc, flavor) => {
acc[flavor.type] = flavor;
return acc;
}, {} as any); // any for now
Is it possible to obtain a const asserted object (map) of flavors after using reduce?
Here's what I tried, but I can see there is a problem with FlavorsMapType
type.
const flavors = [
{ type: 'sweet' },
{ type: 'sour' },
] as const;
type FlavorsType = typeof flavors;
type FlavorsMapType = Record<FlavorsType[number]['type'], FlavorsType[number]>
const flavorsMap = flavors.reduce((acc, flavor) => {
acc[flavor.type] = flavor;
return acc;
}, {} as FlavorsMapType);
const expectedFlavorsMap = {
'sweet': { type: 'sweet' },
'sour': { type: 'sour' }
} as const;
const sweet = flavorsMap['sweet'];
// err, expected type to be the object {type: 'sweet'}
const sweet2: { readonly type: 'sweet' } = flavorsMap['sweet'];
Thanks in advance!