helpertypes/dist/index.d.ts

A collection of TypeScript helper types

/**
 * Makes T a union of T, null, and undefined
 */
export declare type Nullable<T> = T | null | undefined;
/**
 * Makes all properties of T mutable
 */
export declare type Mutable<T> = {
    -readonly [P in keyof T]: T[P];
};
/**
 * Picks the element type of the given iterable.
 * For example, for the given array literal type: ["foo", "bar", "baz"],
 * the type is "foo"|"bar"|"baz"
 */
export declare type ElementOf<Iterable> = Iterable extends (infer ArrayElementType)[] ? ArrayElementType : Iterable extends readonly (infer ReadonlyArrayElementType)[] ? ReadonlyArrayElementType : Iterable extends Set<infer SetElementType> ? SetElementType : Iterable extends string ? Iterable : never;
/**
 * Something that is an array of T's or a single T
 */
export declare type MaybeArray<T> = T[] | T;
/**
 * Ensures that T is an array of the element type of T
 */
export declare type EnsureArray<T> = T extends (infer U)[] ? U[] : T[];
/**
 * A variant of Required where not only the keys are required, but also the values
 */
export declare type RequiredValues<T> = {
    [P in keyof T]-?: Exclude<T[P], null | undefined>;
};
/**
 * Picks only keys for which there is an optional modifier
 */
export declare type PickOptional<T> = Pick<T, Exclude<{
    [K in keyof T]: T extends Record<K, T[K]> ? never : K;
}[keyof T], undefined>>;
/**
 * Picks only keys for which there is no optional modifier
 */
export declare type PickRequired<T> = Pick<T, Exclude<{
    [K in keyof T]: T extends Record<K, T[K]> ? K : never;
}[keyof T], undefined>>;
/**
 * Picks those keys from A that intersects with those from B
 */
export declare type PickIntersectingKeys<A, B> = Pick<A, Exclude<{
    [Key in keyof A]: Key extends keyof B ? Key : never;
}[keyof A], undefined>>;
/**
 * Picks from T the properties for which their type matches Type
 */
export declare type PickMembersOfType<T, Type> = Pick<T, {
    [Key in keyof T]: T[Key] extends Type ? Key : never;
}[keyof T]>;
export declare type PickMembersOfNotOfType<T, Type> = Pick<T, {
    [Key in keyof T]: T[Key] extends Type ? never : T[Key] extends Type | undefined ? never : Key;
}[keyof T]>;
/**
 * Builds up a lookup path into a record via tuple elements. For example, for the record `{ a: {b: {c: string}}}`, a valid value could be `["a", "b", "c"]`
 * It takes as the second optional type argument the maximum depth it can recursively descent into the target object (default: 10).
 * When an Array is discovered, indexes into the array can be provided. For example, for the record `{a: {foo: string}[]}`, a value like `["a", 0, "foo"]` is allowed.
 */
export declare type ObjectLookupTuple<T, MaxDepth extends number = 10> = ObjectLookupTupleHelper<T, [], MaxDepth>;
declare type ObjectLookupTupleHelper<T, Acc extends PropertyKey[], MaxDepth extends number, CurrentDepth extends number = 0> = {
    [Key in keyof T]: CurrentDepth extends MaxDepth ? [...Acc, Key] : T[Key] extends IgnoredLookupValue ? [...Acc, Key] : T[Key] extends (infer El)[] | readonly (infer El)[] ? [...Acc, Key] | ObjectLookupTupleHelper<El, [...Acc, Key, number], MaxDepth, Next<CurrentDepth>> : [...Acc, Key] | ObjectLookupTupleHelper<NonNullable<T[Key]>, [...Acc, Key, number], MaxDepth, Next<CurrentDepth>>;
}[keyof T];
/**
 * A variant of ObjectLookupTuple that will walk into arrays and allow looking up members of their records as part of the lookup path. For
 * example, for the record `{a: {foo: string}[]}`, a value like `["a", "foo"]` is allowed, even though 'foo' is part of a record within an array
 */
export declare type ArrayPiercingObjectLookupTuple<T, MaxDepth extends number = 10> = ArrayPiercingObjectLookupTupleHelper<T, [], MaxDepth>;
declare type ArrayPiercingObjectLookupTupleHelper<T, Acc extends PropertyKey[], MaxDepth extends number, CurrentDepth extends number = 0> = {
    [Key in keyof T]: CurrentDepth extends MaxDepth ? [...Acc, Key] : T[Key] extends IgnoredLookupValue ? [...Acc, Key] : T[Key] extends (infer El)[] | readonly (infer El)[] ? [...Acc, Key] | ArrayPiercingObjectLookupTupleHelper<El, [...Acc, Key], MaxDepth, Next<CurrentDepth>> : [...Acc, Key] | ArrayPiercingObjectLookupTupleHelper<NonNullable<T[Key]>, [...Acc, Key], MaxDepth, Next<CurrentDepth>>;
}[keyof T];
/**
 * Behaves similar to ObjectLookupTuple, but builds up strings that dot into objects. For example, for the record `{ a: {b: {c: string}}}`, a valid value could be `a.b.c`
 */
export declare type ObjectLookupString<T, MaxDepth extends number = 10, StopAtArrays extends boolean = false> = ObjectLookupStringHelper<T, ``, MaxDepth, 0, StopAtArrays>;
declare type MaybeSuffixWithDot<T extends string> = T extends `` ? T : `${T}.`;
declare type ObjectLookupStringHelper<T, Acc extends string, MaxDepth extends number, CurrentDepth extends number = 0, StopAtArrays extends boolean = false> = {
    [Key in keyof T]: Key extends string ? CurrentDepth extends MaxDepth ? `${MaybeSuffixWithDot<Acc>}${Key}` : T[Key] extends IgnoredLookupValue ? `${MaybeSuffixWithDot<Acc>}${Key}` : T[Key] extends (infer El)[] | readonly (infer El)[] ? StopAtArrays extends true ? `${MaybeSuffixWithDot<Acc>}${Key}` : `${MaybeSuffixWithDot<Acc>}${Key}.${number}` | El extends IgnoredLookupValue ? `${MaybeSuffixWithDot<Acc>}${Key}.${number}` : ObjectLookupStringHelper<El, `${MaybeSuffixWithDot<Acc>}${Key}.${number}`, MaxDepth, Next<CurrentDepth>, StopAtArrays> : `${MaybeSuffixWithDot<Acc>}${Key}` | ObjectLookupStringHelper<NonNullable<T[Key]>, `${MaybeSuffixWithDot<Acc>}${Key}`, MaxDepth, Next<CurrentDepth>, StopAtArrays> : never;
}[keyof T];
/**
 * A variant of Partial that is deep.
 * This means that every value is a partial recursively
 * while still preserving primitive or built-in types as they are
 */
export declare type PartialDeep<T, MaxDepth extends number = 10, CurrentDepth extends number = 0> = CurrentDepth extends MaxDepth ? T : T extends IgnoredLookupValue ? T : T extends (infer ArrayElement)[] ? PartialDeep<ArrayElement, MaxDepth, Next<CurrentDepth>>[] : T extends readonly (infer ReadonlyArrayElement)[] ? readonly PartialDeep<ReadonlyArrayElement, MaxDepth, Next<CurrentDepth>>[] : T extends Iterable<infer IterableType> ? Iterable<PartialDeep<IterableType, MaxDepth, Next<CurrentDepth>>> : {
    [P in keyof T]?: PartialDeep<T[P], MaxDepth, Next<CurrentDepth>>;
};
/**
 * A variant of Required that is deep.
 * This means that every key is required recursively
 * while still preserving primitive or built-in types as they are
 */
export declare type RequiredDeep<T, MaxDepth extends number = 10, CurrentDepth extends number = 0> = CurrentDepth extends MaxDepth ? T : T extends IgnoredLookupValue ? T : T extends (infer ArrayElement)[] ? RequiredDeep<ArrayElement, MaxDepth, Next<CurrentDepth>>[] : T extends readonly (infer ReadonlyArrayElement)[] ? readonly RequiredDeep<ReadonlyArrayElement, MaxDepth, Next<CurrentDepth>>[] : T extends Iterable<infer IterableType> ? Iterable<RequiredDeep<IterableType, MaxDepth, Next<CurrentDepth>>> : {
    [P in keyof T]-?: RequiredDeep<T[P], MaxDepth, Next<CurrentDepth>>;
};
/**
 * A partial of T except for the keys given in K
 */
export declare type PartialExcept<T, K extends keyof T> = Omit<Partial<T>, K> & Pick<T, K>;
/**
 * A partial of T except for the keys given in K
 */
export declare type PartialDeepExcept<T, K extends keyof T> = Omit<PartialDeep<T>, K> & Pick<T, K>;
/**
 * Require all keys in T, except for the keys given in K
 */
export declare type RequiredExcept<T, K extends keyof T> = Omit<Required<T>, K> & Pick<T, K>;
/**
 * Splits a record into all of its possible property intersections.
 * For example, for the record {a: 1; b: 2>}, splitting the record will
 * get the type {a: 1} | {b: 2} back.
 */
export declare type SplitRecord<T, U = T> = Exclude<{
    [Key in keyof T]: {
        [K in Key]: K extends keyof U ? T[K] : never;
    };
}[keyof T], undefined>;
/**
 * A variant of `SplitRecord` that includes all similar keys.
 * See the documentation for `SimilarObjectKeys` for more details.
 */
export declare type SplitRecordWithSimilarKeys<T, U = T> = Exclude<{
    [Key in keyof T]: Key extends keyof U ? SimilarObjectKeys<T, Key & string> : never;
}[keyof T], undefined>;
/**
 * Selects only the properties from an object for which the keys include the substring(s) given in U.
 * For example, for the object {foo: 1, fooBar: 2, barFoo: 3, baz: 4}, a value of "foo" for U will return an object with only the keys "foo", "fooBar", and "barFoo"
 */
export declare type SimilarObjectKeys<T, U extends keyof T & string> = PickMembersOfNotOfType<{
    [TKey in keyof T]: TKey extends U ? T[TKey] : TKey extends `${infer _Prefix}${Capitalize<U>}` ? T[TKey] | undefined : TKey extends `${infer _Prefix}${U}` ? T[TKey] | undefined : TKey extends `${U}${infer _Suffix}` ? T[TKey] | undefined : never;
}, never>;
/**
 * An arbitrary Function that takes any amount of arguments and returns anything
 */
export declare type ArbitraryFunction<ReturnType = unknown> = (...args: never[]) => ReturnType;
export declare type ArbitraryConstructor<T> = new (...args: never[]) => T;
/**
 * Gets the length of T
 */
export declare type GetLength<T extends unknown[]> = T extends {
    length: infer L;
} ? L : never;
/**
 * Gets the first element of T
 */
export declare type GetFirst<T extends unknown[]> = T[0];
/**
 * Gets the last element of T
 */
export declare type GetLast<T extends unknown[]> = T[Prev<GetLength<T>>];
/**
 * Gets the Nth parameter of the given function
 */
export declare type NthParameter<T extends ArbitraryFunction, Parameter extends number> = Parameters<T>[Parameter];
/**
 * Gets the first parameter of the given function
 */
export declare type FirstParameter<T extends ArbitraryFunction> = GetFirst<Parameters<T>>;
/**
 * Gets the last parameter of the given function
 */
export declare type LastParameter<T extends ArbitraryFunction> = GetLast<Parameters<T>>;
export declare type UncapitalizeKeys<T> = {
    [Key in keyof T as Uncapitalize<string & Key>]: T[Key];
};
export declare type CapitalizeKeys<T> = {
    [Key in keyof T as Capitalize<string & Key>]: T[Key];
};
export declare type LowercaseKeys<T> = {
    [Key in keyof T as Lowercase<string & Key>]: T[Key];
};
export declare type UppercaseKeys<T> = {
    [Key in keyof T as Uppercase<string & Key>]: T[Key];
};
export declare type PrefixObjectKeys<T, Prefix extends string, EnsureCamelCase = false> = {
    [Key in keyof T as SuffixKey<Key & string, Prefix, EnsureCamelCase>]: T[Key];
};
export declare type SuffixObjectKeys<T, Suffix extends string, EnsureCamelCase = false> = {
    [Key in keyof T as PrefixKey<Key & string, Suffix, EnsureCamelCase>]: T[Key];
};
export declare type PrefixKey<T extends string, Prefix extends string, EnsureCamelCase = false> = `${Prefix}${EnsureCamelCase extends true ? Capitalize<T> : T}`;
export declare type SuffixKey<T extends string, Suffix extends string, EnsureCamelCase = false> = `${T}${EnsureCamelCase extends true ? Capitalize<Suffix> : Suffix}`;
export declare type Prev<T extends number> = [
    -1,
    0,
    1,
    2,
    3,
    4,
    5,
    6,
    7,
    8,
    9,
    10,
    11,
    12,
    13,
    14,
    15,
    16,
    17,
    18,
    19,
    20,
    21,
    22,
    23,
    24,
    25,
    26,
    27,
    28,
    29,
    30,
    31,
    32,
    33,
    34,
    35,
    36,
    37,
    38,
    39,
    40,
    41,
    42,
    43,
    44,
    45,
    46,
    47,
    48,
    49,
    50,
    51,
    52,
    53,
    54,
    55,
    56,
    57,
    58,
    59,
    60,
    61,
    62,
    63,
    64,
    65,
    66,
    67,
    68,
    69,
    70,
    71,
    72,
    73,
    74,
    75,
    76,
    77,
    78,
    79,
    80,
    81,
    82,
    83,
    84,
    85,
    86,
    87,
    88,
    89,
    90,
    91,
    92,
    93,
    94,
    95,
    96,
    97,
    98,
    99,
    100
][T];
export declare type Next<T extends number> = [
    1,
    2,
    3,
    4,
    5,
    6,
    7,
    8,
    9,
    10,
    11,
    12,
    13,
    14,
    15,
    16,
    17,
    18,
    19,
    20,
    21,
    22,
    23,
    24,
    25,
    26,
    27,
    28,
    29,
    30,
    31,
    32,
    33,
    34,
    35,
    36,
    37,
    38,
    39,
    40,
    41,
    42,
    43,
    44,
    45,
    46,
    47,
    48,
    49,
    50,
    51,
    52,
    53,
    54,
    55,
    56,
    57,
    58,
    59,
    60,
    61,
    62,
    63,
    64,
    65,
    66,
    67,
    68,
    69,
    70,
    71,
    72,
    73,
    74,
    75,
    76,
    77,
    78,
    79,
    80,
    81,
    82,
    83,
    84,
    85,
    86,
    87,
    88,
    89,
    90,
    91,
    92,
    93,
    94,
    95,
    96,
    97,
    98,
    99,
    100,
    101
][T];
/**
 * A type indicating something that shouldn't be traversed into when mapping over objects, lists, or other similar data structures
 */
export declare type IgnoredLookupValue = string | number | bigint | symbol | boolean | undefined | null | Date | RegExp | CallableFunction | Set<unknown> | WeakSet<never> | Map<unknown, unknown> | WeakMap<never, unknown>;
export {};
//# sourceMappingURL=index.d.ts.map