TS Exclude Keys with Dot Notation
When working with TypeScript, you may come across situations where you need to exclude keys with dot notation. This can be useful when you want to filter out certain properties from an object or when you want to create a new object without specific keys.
Solution 1: Using the Omit Utility Type
One way to exclude keys with dot notation is by using the Omit
utility type provided by TypeScript. The Omit
utility type allows you to create a new type by excluding specific keys from an existing type.
Here’s an example:
type MyType = {
foo: string;
bar: number;
nested: {
baz: boolean;
};
};
type ExcludeKeys = Omit;
const obj: ExcludeKeys = {
foo: 'Hello',
bar: 42,
};
In this example, we have a type MyType
with three properties: foo
, bar
, and nested
. The nested
property has a nested object with a property baz
. We want to exclude the nested.baz
key from the new type ExcludeKeys
.
The resulting ExcludeKeys
type will only have the foo
and bar
properties, excluding nested.baz
. We can then create an object obj
of type ExcludeKeys
with the excluded keys.
Solution 2: Using Object Destructuring
Another way to exclude keys with dot notation is by using object destructuring. With object destructuring, you can create a new object without specific keys from an existing object.
Here’s an example:
const obj = {
foo: 'Hello',
bar: 42,
nested: {
baz: true,
},
};
const { nested: { baz, ...rest }, ...newObj } = obj;
In this example, we have an object obj
with three properties: foo
, bar
, and nested
. We want to exclude the nested.baz
key from the new object newObj
.
By using object destructuring, we can assign the value of nested.baz
to a variable baz
and exclude it from the rest of the nested object by using the ...rest
syntax. We can also exclude the entire nested
property from the new object newObj
.
Conclusion
Excluding keys with dot notation in TypeScript can be achieved using the Omit
utility type or object destructuring. The Omit
utility type allows you to create a new type by excluding specific keys, while object destructuring allows you to create a new object without specific keys.
Choose the solution that best fits your needs and implement it in your TypeScript code to exclude keys with dot notation.
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