TypeScript-Handbook
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Misstatement in definition of `Partial<T>`
The definition of Partial<T>
states:
Constructs a type with all properties of T set to optional. This utility will return a type that represents all subsets of a given type.
To paraphrase Inigo Montoya: You use the word "subset". I do not think it means what you think it means.
A "type with all properties of T set to optional" does not represent subsets of T.
Examples of "subsets of a given type":
- given type:
real number
, some subsets:rational number
,integer
- given type:
number | string | null
, some subsets:number
,number | null
I know what the author is trying to say, but can't come up with the right words, though I probably should have spent more time on that than what I've put into this Issue so far 😂.
I know what the author is trying to say,
Now that you've brought it up, I've realized I have no idea what the author is trying to say in the second sentence. Partial<T>
only returns the params of the targeted type with the optional
flag on each one, doesn't it? Does something else happen if the targeted type isn't an object literal?