Consider a scenario where I have a generic type defined as follows:
type Item<T> = {a:T; B:T}
In this case, I aim to automatically determine an object with consistent fields types without explicitly stating the generic type:
const items: Record<string, Item<?>> = {
first: {a:1, b:2},
second: {a:'asd'; b:'asd'}
third: {a:1; b:'qwe'} // The error should occur here because the generic type is not specified
} as const
Here is some sample code that demonstrates the usage of generic types in TypeScript:
type Item<T> = {a:T; b:T}
// Define different item types
type StringItem = Item<string>
type NumberItem = Item<number>
// Combine all possible item types using union
type Items =
| StringItem
| NumberItem
// Intentionally create a compile error by not agreeing on generic type
const items: Record<string, Items> = {
first: {a:1, b:2},
second: {a:'abc', b:'def'},
third: {a:4, b:'ghi'} // Compile error should occur here due to conflicting generic types
} as const
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