Consider the scenario where a variable may hold either a string or an object with properties like this:
value?: string | { name: string, type: string }
Attempting to work with it below leads to a compile error:
console.log(value?.name || value)
console.log(value?.type)
Any suggestions on how to properly handle such a variable that can have different types?
If you encounter this situation, try the following:
console.log(typeof value === 'string' ? value : value?.name)
Typescript has the ability to refine types using type-guards; refer to this resource for more insights.
There are a couple of choices available to you
console.log(typeof value === 'string' ? value : value.name);
Since you have used ?: in the definition for this value (allowing undefined) and considering that the console is only being used for a simple example here
if (value === undefined) {
} else if (typeof value === 'string') {
} else {
}
This approach would be most suitable.
The issue you encountered is mainly due to both values for the value variable being objects and TypeScript recognizing that the types are not compatible, prompting you to narrow them down manually
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