When utilizing TypeScript, the following code:
const x = 1;
Typically infers the type of x as number. Is it possible to specify that TypeScript infer the type as 1? (Restricting it to only be assigned the value 1).
Similarly, with this code block:
const x: {
name: 'Name',
age: 0,
}
Is there a way to have TypeScript infer the type of x as:
{
name: 'Name',
age: 0,
}
I recall seeing a keyword for this functionality before, but I'm unable to locate it now.
Regarding x, it seems your assumption is incorrect
The type of x appears to be inferred as a number
This scenario would only be true if you had used the let keyword. However, since you opted for the const keyword, the variable cannot be reassigned. Therefore, what you desire to occur is already taking place.
When you declare const x = 1, the type is inferred as 1 rather than number.
To achieve similar results for y, consider utilizing const assertions
const y = {
name: 'Name',
age: 0,
} as const;
This method creates an immutable object where y.name is assigned the type 'Name' and y.age is assigned the type 0
Implement constant contexts:
const a = 5 as const;
const b = {
title: 'Title',
count: 10,
} as const
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