This solution is generated by ChatGPT, correctness is not guaranteed.
AI solution for TypeScript puzzle on BFE.dev
55. implement StringToNumber<S>
type StringToNumber<S extends string> = S extends `${infer First}${infer Rest}`
? First extends keyof Numbers
? Numbers[First] extends never
? never
: Numbers[First] extends number
? `${Numbers[First]}${StringToNumber<Rest>}`
: never
: never
: 0;
type Numbers = {
'0': 0;
'1': 1;
'2': 2;
'3': 3;
'4': 4;
'5': 5;
'6': 6;
'7': 7;
'8': 8;
'9': 9;
};
In the above solution, we use conditional types to check whether the first character of the string is a valid digit (0-9). Then, we recursively call the StringToNumber
type to convert the rest of the string to a number. If the first character is not a valid digit, then we return never
type to indicate a type error.
We also define a Numbers
type which associates the digits 0-9 with their respective numeric types. This type is used in validating the first character of the string.