@xylabs/typeof
Advanced tools
Base functionality used throughout XY Labs TypeScript/JavaScript libraries
@xylabs/typeof
function ifDefined<T>(value, func): T | undefined;
T
T
(value) => void
T | undefined
function ifTypeOf<T, R>(
typeName,
value,
trueFunc,
isFunc?): R | undefined;
T
R
unknown
(value) => R
(value) => boolean
R | undefined
function isArray(value): value is readonly unknown[];
unknown
value is readonly unknown[]
function isArray<T>(value): value is Extract<T, readonly unknown[]>;
T
T
value is Extract<T, readonly unknown[]>
function isArrayBufferView(value): value is ArrayBufferView<ArrayBufferLike>;
unknown
value is ArrayBufferView<ArrayBufferLike>
function isArrayBufferView<T>(value): value is Extract<T, ArrayBufferView<ArrayBufferLike>>;
T extends ArrayBufferView<ArrayBufferLike>
T
value is Extract<T, ArrayBufferView<ArrayBufferLike>>
function isBigInt(value): value is bigint;
unknown
value is bigint
function isBigInt<T>(value): value is Extract<T, bigint>;
T extends bigint
T
value is Extract<T, bigint>
function isBlob(value): value is Blob;
unknown
value is Blob
function isBlob<T>(value): value is Extract<T, Blob>;
T extends Blob
T
value is Extract<T, Blob>
function isBoolean(value): value is boolean;
unknown
value is boolean
function isBoolean<T>(value): value is Extract<T, boolean>;
T extends boolean
T
value is Extract<T, boolean>
function isDataView(value): value is DataView<ArrayBufferLike>;
unknown
value is DataView<ArrayBufferLike>
function isDataView<T>(value): value is Extract<T, DataView<ArrayBufferLike>>;
T
T
value is Extract<T, DataView<ArrayBufferLike>>
function isDate(value): value is Date;
unknown
value is Date
function isDate<T>(value): value is Extract<T, Date>;
T
T
value is Extract<T, Date>
function isDateString(value): value is string;
unknown
value is string
function isDateString<T>(value): value is Extract<T, string>;
T
T
value is Extract<T, string>
function isDefined<T>(value): value is Exclude<T, undefined>;
T
T
value is Exclude<T, undefined>
function isDefinedNotNull<T>(value): value is Exclude<T, null | undefined>;
T
T
value is Exclude<T, null | undefined>
function isEmpty<T>(value): value is T;
T
unknown
value is T
function isEmpty<K, V, T>(value): value is Extract<T, Record<K, never>>;
K extends RecordKey
V
T extends Record<K, V>
T
value is Extract<T, Record<K, never>>
function isEmpty<T>(value): value is Extract<T, never[]>;
T extends unknown[]
T
value is Extract<T, never[]>
function isEmptyArray(value): value is [];
unknown
value is []
function isEmptyArray<T>(value): value is Extract<T, unknown[]>;
T extends unknown[]
T
value is Extract<T, unknown[]>
function isEmptyObject(value): value is {};
unknown
value is {}
function isEmptyObject<K, V, T>(value): value is Extract<T, Record<K, never>>;
K extends RecordKey
V
T extends Record<K, V>
T
value is Extract<T, Record<K, never>>
function isEmptyString(value): value is "";
unknown
value is ""
function isEmptyString<T>(value): value is Extract<T, "">;
T extends string
T
value is Extract<T, "">
function isError(value): value is Error;
unknown
value is Error
function isError<T>(value): value is Extract<T, Error>;
T
T
value is Extract<T, Error>
function isFalsy<T>(value): value is Extract<T, false | "" | 0 | 0n | null | undefined>;
T
T
value is Extract<T, false | "" | 0 | 0n | null | undefined>
function isFalsy<T>(value): value is Extract<T, false>;
T extends boolean
T
value is Extract<T, false>
function isFalsy<T>(value): value is Extract<T, 0>;
T extends number
T
value is Extract<T, 0>
function isFalsy<T>(value): value is Extract<T, 0n>;
T extends bigint
T
value is Extract<T, 0n>
function isFalsy<T>(value): value is Extract<T, null>;
T extends null
T
value is Extract<T, null>
function isFalsy<T>(value): value is Extract<T, undefined>;
T extends undefined
T
value is Extract<T, undefined>
function isFalsy<T>(value): value is Extract<T, "">;
T extends string
T
value is Extract<T, "">
function isFile(value): value is File;
unknown
value is File
function isFile<T>(value): value is Extract<T, File>;
T extends File
T
value is Extract<T, File>
function isFunction(value): value is AnyFunction;
unknown
value is AnyFunction
function isFunction<T>(value): value is Extract<T, AnyFunction>;
T extends AnyFunction
T
value is Extract<T, AnyFunction>
function isMap(value): value is Map<unknown, unknown>;
unknown
value is Map<unknown, unknown>
function isMap<K, V, T>(value): value is Extract<T, Map<K, V>>;
K
V
T extends Map<K, V>
T
value is Extract<T, Map<K, V>>
function isNull(value): value is null;
unknown
value is null
function isNull<T>(value): value is Extract<T, null>;
T
T
value is Extract<T, null>
function isNumber(value): value is number;
unknown
value is number
function isNumber<T>(value): value is Extract<T, number>;
T extends number
T
value is Extract<T, number>
function isObject(value): value is object;
unknown
value is object
function isObject<T>(value): value is Extract<T, object>;
T extends object
T
value is Extract<T, object>
function isPopulatedArray(value): value is readonly unknown[];
unknown
value is readonly unknown[]
function isPopulatedArray<T>(value): value is Extract<T, readonly unknown[]>;
T extends unknown[]
T
value is Extract<T, readonly unknown[]>
function isPromise(value): value is Promise<unknown>;
unknown
value is Promise<unknown>
function isPromise<T>(value): value is Extract<T, Promise<unknown>>;
T
T
value is Extract<T, Promise<unknown>>
function isPromiseLike(value): value is Promise<unknown>;
unknown
value is Promise<unknown>
function isPromiseLike<T>(value): value is Extract<T, Promise<unknown>>;
T
T
value is Extract<T, Promise<unknown>>
function isRegExp(value): value is RegExp;
unknown
value is RegExp
function isRegExp<T>(value): value is Extract<T, RegExp>;
T extends RegExp
T
value is Extract<T, RegExp>
function isSet(value): value is Set<unknown>;
unknown
value is Set<unknown>
function isSet<T>(value): value is Extract<T, Set<unknown>>;
T extends Set<unknown>
unknown
value is Extract<T, Set<unknown>>
function isString(value): value is string;
unknown
value is string
function isString<T>(value): value is Extract<T, string>;
T extends string
T
value is Extract<T, string>
function isSymbol(value): value is symbol;
unknown
value is symbol
function isSymbol<T>(value): value is Extract<T, symbol>;
T extends symbol
T
value is Extract<T, symbol>
function isTruthy<T>(value): value is Exclude<T, false | "" | 0 | 0n | null | undefined>;
T
T
value is Exclude<T, false | "" | 0 | 0n | null | undefined>
function isTruthy<T>(value): value is Extract<T, true>;
T extends boolean
T
value is Extract<T, true>
function isTruthy<T>(value): value is Extract<T, number>;
T extends number
T
value is Extract<T, number>
function isTruthy<T>(value): value is Extract<T, bigint>;
T extends bigint
T
value is Extract<T, bigint>
function isTruthy<T>(value): value is Extract<T, null>;
T extends null
T
value is Extract<T, null>
function isTruthy<T>(value): value is Extract<T, undefined>;
T extends undefined
T
value is Extract<T, undefined>
function isTruthy<T>(value): value is Extract<T, string>;
T extends string
T
value is Extract<T, string>
function isType(value, expectedType): boolean;
unknown
boolean
function isTypedArray(value): value is TypedArray;
unknown
value is TypedArray
function isTypedKey(value): value is string | number | symbol;
unknown
value is string | number | symbol
function isTypedObject(value): value is TypedObject;
unknown
value is TypedObject
function isTypedValue(value): value is TypedValue;
unknown
value is TypedValue
function isUndefined(value): value is undefined;
unknown
value is undefined
function isUndefined<T>(value): value is Extract<T, undefined>;
T
T
value is Extract<T, undefined>
function isUndefinedOrNull(value): value is null | undefined;
unknown
value is null | undefined
function isUndefinedOrNull<T>(value): value is Extract<T, null | undefined>;
T
T
value is Extract<T, null | undefined>
function isValidTypedFieldPair(pair): pair is [key: string | number | symbol, value: TypedValue];
[unknown, unknown]
pair is [key: string | number | symbol, value: TypedValue]
function isWeakMap(value): value is WeakMap<WeakKey, unknown>;
unknown
value is WeakMap<WeakKey, unknown>
function isWeakMap<K, V, T>(value): value is Extract<T, WeakMap<K, V>>;
K extends WeakKey
V
T extends WeakMap<K, V>
T
value is Extract<T, WeakMap<K, V>>
function isWeakSet(value): value is WeakSet<WeakKey>;
unknown
value is WeakSet<WeakKey>
function isWeakSet<K, T>(value): value is Extract<T, WeakSet<K>>;
K extends WeakKey
T extends WeakSet<K>
T
value is Extract<T, WeakSet<K>>
function typeOf<T>(item): TypeOfTypes;
T
T
function validateType<T>(
typeName,
value,
optional?): [T | undefined, Error[]];
T
T
boolean = false
[T | undefined, Error[]]
type AnyFunction = (...args) => unknown;
...unknown[]
unknown
type Brand<T, B> = T & { [K in keyof B]: B[K] };
T
B
type FieldType =
| "string"
| "number"
| "object"
| "symbol"
| "undefined"
| "null"
| "array"
| "function";
type IdentityFunction<T> = (value) => value is T;
T
unknown
value is T
type ObjectTypeShape = Record<string | number | symbol, FieldType>;
type RecordKey = string | number | symbol;
type TypeOfTypes =
| "string"
| "number"
| "object"
| "array"
| "buffer"
| "null"
| "undefined"
| "bigint"
| "boolean"
| "function"
| "symbol";
type TypedArray = TypedValue[];
type TypedKey<T> = T extends string ? T : string | number | symbol;
T extends string | void = void
type TypedObject =
| {
[key: string | number | symbol]: TypedValue;
}
| object;
type TypedValue =
| bigint
| string
| number
| boolean
| null
| TypedObject
| TypedArray
| Function
| symbol
| undefined;
Part of sdk-js
See the LICENSE file for license details
FAQs
Base functionality used throughout XY Labs TypeScript/JavaScript libraries
The npm package @xylabs/typeof receives a total of 1,329 weekly downloads. As such, @xylabs/typeof popularity was classified as popular.
We found that @xylabs/typeof demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 5 open source maintainers collaborating on the project.
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