Assert

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Assertion utilities.

Installation

npm install @stdlib/assert

Usage

var assert = require( '@stdlib/assert' );

assert

Namespace providing utilities for data type testing and feature detection.

var o = assert;
// returns {...}

To validate the built-in JavaScript data types, the namespace includes the following assertion utilities:

• [isArray( value )][@stdlib/assert/is-array]: test if a value is an array.
• [isBoolean( value )][@stdlib/assert/is-boolean]: test if a value is a boolean.
• [isDateObject( value )][@stdlib/assert/is-date-object]: test if a value is a Date object.
• [isFunction( value )][@stdlib/assert/is-function]: test if a value is a function.
• [isnan( value )][@stdlib/assert/is-nan]: test if a value is NaN.
• [isNull( value )][@stdlib/assert/is-null]: test if a value is null.
• [isNumber( value )][@stdlib/assert/is-number]: test if a value is a number.
• [isObject( value )][@stdlib/assert/is-object]: test if a value is an object.
• [isRegExp( value )][@stdlib/assert/is-regexp]: test if a value is a regular expression.
• [isString( value )][@stdlib/assert/is-string]: test if a value is a string.
• [isSymbol( value )][@stdlib/assert/is-symbol]: test if a value is a symbol.
• [isUndefined( value )][@stdlib/assert/is-undefined]: test if a value is undefined.

For primitive types having corresponding object wrappers, assertion utilities provide isObject and isPrimitive methods to test for either objects or primitives, respectively.

var Boolean = require( '@stdlib/boolean/ctor' );
var isBoolean = require( '@stdlib/assert/is-boolean' );

var bool = isBoolean.isObject( new Boolean( false ) );
// returns true

bool = isBoolean.isObject( false );
// returns false

bool = isBoolean.isPrimitive( false );
// returns true

Many of the assertion utilities have corresponding packages that test whether array elements are of the given data type:

• [isArrayArray( value )][@stdlib/assert/is-array-array]: test if a value is an array of arrays.
• [isBooleanArray( value )][@stdlib/assert/is-boolean-array]: test if a value is an array-like object of booleans.
• [isDateObjectArray( value )][@stdlib/assert/is-date-object-array]: test if a value is an array-like object containing only Date objects.
• [isFunctionArray( value )][@stdlib/assert/is-function-array]: test if a value is an array-like object containing only functions.
• [isNaNArray( value )][@stdlib/assert/is-nan-array]: test if a value is an array-like object containing only NaN values.
• [isNullArray( value )][@stdlib/assert/is-null-array]: test if a value is an array-like object containing only null values.
• [isNumberArray( value )][@stdlib/assert/is-number-array]: test if a value is an array-like object of numbers.
• [isObjectArray( value )][@stdlib/assert/is-object-array]: test if a value is an array-like object containing only objects.
• [isStringArray( value )][@stdlib/assert/is-string-array]: test if a value is an array of strings.
• [isSymbolArray( value )][@stdlib/assert/is-symbol-array]: test if a value is an array-like object containing only symbols.

Where applicable, similar to the assertion utilities for built-in data types, array assertion utilities provides methods for testing for an array of primitives or objects.

var isStringArray = require( '@stdlib/assert/is-string-array' );

var bool = isStringArray( [ 'hello', 'world' ] );
// returns true

bool = isStringArray.primitives( [ 'hello', 'world' ] );
// returns true

bool = isStringArray.objects( [ 'hello', 'world' ] );
// returns false

bool = isStringArray.objects( [ new String( 'hello' ), new String( 'world' ) ] );
// returns true

The namespace also contains utilities to test for numbers within a certain range or for numbers satisfying a particular "type":

• [isCubeNumber( value )][@stdlib/assert/is-cube-number]: test if a value is a cube number.
• [isIntegerArray( value )][@stdlib/assert/is-integer-array]: test if a value is an array-like object containing only integers.
• [isInteger( value )][@stdlib/assert/is-integer]: test if a value is a number having an integer value.
• [isNegativeIntegerArray( value )][@stdlib/assert/is-negative-integer-array]: test if a value is an array-like object containing only negative integers.
• [isNegativeInteger( value )][@stdlib/assert/is-negative-integer]: test if a value is a number having a negative integer value.
• [isNegativeNumberArray( value )][@stdlib/assert/is-negative-number-array]: test if a value is an array-like object containing only negative numbers.
• [isNegativeNumber( value )][@stdlib/assert/is-negative-number]: test if a value is a number having a negative value.
• [isNonNegativeIntegerArray( value )][@stdlib/assert/is-nonnegative-integer-array]: test if a value is an array-like object containing only nonnegative integers.
• [isNonNegativeInteger( value )][@stdlib/assert/is-nonnegative-integer]: test if a value is a number having a nonnegative integer value.
• [isNonNegativeNumberArray( value )][@stdlib/assert/is-nonnegative-number-array]: test if a value is an array-like object containing only nonnegative numbers.
• [isNonNegativeNumber( value )][@stdlib/assert/is-nonnegative-number]: test if a value is a number having a nonnegative value.
• [isNonPositiveIntegerArray( value )][@stdlib/assert/is-nonpositive-integer-array]: test if a value is an array-like object containing only nonpositive integers.
• [isNonPositiveInteger( value )][@stdlib/assert/is-nonpositive-integer]: test if a value is a number having a nonpositive integer value.
• [isNonPositiveNumberArray( value )][@stdlib/assert/is-nonpositive-number-array]: test if a value is an array-like object containing only nonpositive numbers.
• [isNonPositiveNumber( value )][@stdlib/assert/is-nonpositive-number]: test if a value is a number having a nonpositive value.
• [isPositiveIntegerArray( value )][@stdlib/assert/is-positive-integer-array]: test if a value is an array-like object containing only positive integers.
• [isPositiveInteger( value )][@stdlib/assert/is-positive-integer]: test if a value is a number having a positive integer value.
• [isPositiveNumberArray( value )][@stdlib/assert/is-positive-number-array]: test if a value is an array-like object containing only positive numbers.
• [isPositiveNumber( value )][@stdlib/assert/is-positive-number]: test if a value is a number having a positive value.
• [isSafeIntegerArray( value )][@stdlib/assert/is-safe-integer-array]: test if a value is an array-like object containing only safe integers.
• [isSafeInteger( value )][@stdlib/assert/is-safe-integer]: test if a value is a number having a safe integer value.
• [isSquareNumber( value )][@stdlib/assert/is-square-number]: test if a value is a square number.
• [isSquareTriangularNumber( value )][@stdlib/assert/is-square-triangular-number]: test if a value is a square triangular number.
• [isTriangularNumber( value )][@stdlib/assert/is-triangular-number]: test if a value is a triangular number.

The namespace provides utilities for validating typed arrays:

• [isFloat32Array( value )][@stdlib/assert/is-float32array]: test if a value is a Float32Array.
• [isFloat64Array( value )][@stdlib/assert/is-float64array]: test if a value is a Float64Array.
• [isInt16Array( value )][@stdlib/assert/is-int16array]: test if a value is an Int16Array.
• [isInt32Array( value )][@stdlib/assert/is-int32array]: test if a value is an Int32Array.
• [isInt8Array( value )][@stdlib/assert/is-int8array]: test if a value is an Int8Array.
• [isUint16Array( value )][@stdlib/assert/is-uint16array]: test if a value is a Uint16Array.
• [isUint32Array( value )][@stdlib/assert/is-uint32array]: test if a value is a Uint32Array.
• [isUint8Array( value )][@stdlib/assert/is-uint8array]: test if a value is a Uint8Array.
• [isUint8ClampedArray( value )][@stdlib/assert/is-uint8clampedarray]: test if a value is a Uint8ClampedArray.

The namespace includes utilities for validating ndarrays (n-dimensional arrays).

• [isCentrosymmetricMatrix( value )][@stdlib/assert/is-centrosymmetric-matrix]: test if a value is a centrosymmetric matrix.
• [isComplex128MatrixLike( value )][@stdlib/assert/is-complex128matrix-like]: test if a value is a 2-dimensional ndarray-like object containing double-precision complex floating-point numbers.
• [isComplex128ndarrayLike( value )][@stdlib/assert/is-complex128ndarray-like]: test if a value is an ndarray-like object containing double-precision complex floating-point numbers.
• [isComplex128VectorLike( value )][@stdlib/assert/is-complex128vector-like]: test if a value is a 1-dimensional ndarray-like object containing double-precision complex floating-point numbers.
• [isComplex64MatrixLike( value )][@stdlib/assert/is-complex64matrix-like]: test if a value is a 2-dimensional ndarray-like object containing single-precision complex floating-point numbers.
• [isComplex64ndarrayLike( value )][@stdlib/assert/is-complex64ndarray-like]: test if a value is an ndarray-like object containing single-precision complex floating-point numbers.
• [isComplex64VectorLike( value )][@stdlib/assert/is-complex64vector-like]: test if a value is a 1-dimensional ndarray-like object containing single-precision complex floating-point numbers.
• [isFloat32MatrixLike( value )][@stdlib/assert/is-float32matrix-like]: test if a value is a 2-dimensional ndarray-like object containing single-precision floating-point numbers.
• [isFloat32ndarrayLike( value )][@stdlib/assert/is-float32ndarray-like]: test if a value is an ndarray-like object containing single-precision floating-point numbers.
• [isFloat32VectorLike( value )][@stdlib/assert/is-float32vector-like]: test if a value is a 1-dimensional ndarray-like object containing single-precision floating-point numbers.
• [isFloat64MatrixLike( value )][@stdlib/assert/is-float64matrix-like]: test if a value is a 2-dimensional ndarray-like object containing double-precision floating-point numbers.
• [isFloat64ndarrayLike( value )][@stdlib/assert/is-float64ndarray-like]: test if a value is an ndarray-like object containing double-precision floating-point numbers.
• [isFloat64VectorLike( value )][@stdlib/assert/is-float64vector-like]: test if a value is a 1-dimensional ndarray-like object containing double-precision floating-point numbers.
• [isMatrixLike( value )][@stdlib/assert/is-matrix-like]: test if a value is 2-dimensional ndarray-like object.
• [isndarrayLike( value )][@stdlib/assert/is-ndarray-like]: test if a value is ndarray-like.
• [isNonSymmetricMatrix( value )][@stdlib/assert/is-nonsymmetric-matrix]: test if a value is a non-symmetric matrix.
• [isPersymmetricMatrix( value )][@stdlib/assert/is-persymmetric-matrix]: test if a value is a persymmetric matrix.
• [isSkewCentrosymmetricMatrix( value )][@stdlib/assert/is-skew-centrosymmetric-matrix]: test if a value is a skew-centrosymmetric matrix.
• [isSkewPersymmetricMatrix( value )][@stdlib/assert/is-skew-persymmetric-matrix]: test if a value is a skew-persymmetric matrix.
• [isSkewSymmetricMatrix( value )][@stdlib/assert/is-skew-symmetric-matrix]: test if a value is a skew-symmetric matrix.
• [isSquareMatrix( value )][@stdlib/assert/is-square-matrix]: test if a value is a 2-dimensional ndarray-like object having equal dimensions.
• [isSymmetricMatrix( value )][@stdlib/assert/is-symmetric-matrix]: test if a value is a symmetric matrix.
• [isVectorLike( value )][@stdlib/assert/is-vector-like]: test if a value is a 1-dimensional ndarray-like object.

The namespace includes utilities for validating complex numbers and arrays of complex numbers:

• [isComplexLike( value )][@stdlib/assert/is-complex-like]: test if a value is a complex number-like object.
• [isComplexTypedArrayLike( value )][@stdlib/assert/is-complex-typed-array-like]: test if a value is complex-typed-array-like.
• [isComplexTypedArray( value )][@stdlib/assert/is-complex-typed-array]: test if a value is a complex typed array.
• [isComplex( value )][@stdlib/assert/is-complex]: test if a value is a 64-bit or 128-bit complex number.
• [isComplex128( value )][@stdlib/assert/is-complex128]: test if a value is a 128-bit complex number.
• [isComplex128Array( value )][@stdlib/assert/is-complex128array]: test if a value is a Complex128Array.
• [isComplex64( value )][@stdlib/assert/is-complex64]: test if a value is a 64-bit complex number.
• [isComplex64Array( value )][@stdlib/assert/is-complex64array]: test if a value is a Complex64Array.

The namespace includes utilities for validating other special arrays or buffers:

• [isAccessorArray( value )][@stdlib/assert/is-accessor-array]: test if a value is an array-like object supporting the accessor (get/set) protocol.
• [isArrayLength( value )][@stdlib/assert/is-array-length]: test if a value is a valid array length.
• [isArrayLikeObject( value )][@stdlib/assert/is-array-like-object]: test if a value is an array-like object.
• [isArrayLike( value )][@stdlib/assert/is-array-like]: test if a value is array-like.
• [isArrayBufferView( value )][@stdlib/assert/is-arraybuffer-view]: test if a value is an ArrayBuffer view.
• [isArrayBuffer( value )][@stdlib/assert/is-arraybuffer]: test if a value is an ArrayBuffer.
• [isBetweenArray( value, a, b[, left, right] )][@stdlib/assert/is-between-array]: test if a value is an array-like object where every element is between two values.
• [isBigInt64Array( value )][@stdlib/assert/is-bigint64array]: test if a value is a BigInt64Array.
• [isBigUint64Array( value )][@stdlib/assert/is-biguint64array]: test if a value is a BigUint64Array.
• [isCircularArray( value )][@stdlib/assert/is-circular-array]: test if a value is an array containing a circular reference.
• [isEmptyArrayLikeObject( value )][@stdlib/assert/is-empty-array-like-object]: test if a value is an empty array-like object.
• [isEmptyArray( value )][@stdlib/assert/is-empty-array]: test if a value is an empty array.
• [isFalsyArray( value )][@stdlib/assert/is-falsy-array]: test if a value is an array-like object containing only falsy values.
• [isFiniteArray( value )][@stdlib/assert/is-finite-array]: test if a value is an array-like object containing only finite numbers.
• [isNumericArray( value )][@stdlib/assert/is-numeric-array]: test if a value is a numeric array.
• [isPlainObjectArray( value )][@stdlib/assert/is-plain-object-array]: test if a value is an array-like object containing only plain objects.
• [isProbabilityArray( value )][@stdlib/assert/is-probability-array]: test if a value is an array-like object containing only probabilities.
• [isSameArray( v1, v2 )][@stdlib/assert/is-same-array]: test if two arguments are both generic arrays and have the same values.
• [isSameComplex128Array( v1, v2 )][@stdlib/assert/is-same-complex128array]: test if two arguments are both Complex128Arrays and have the same values.
• [isSameComplex64Array( v1, v2 )][@stdlib/assert/is-same-complex64array]: test if two arguments are both Complex64Arrays and have the same values.
• [isSameFloat32Array( v1, v2 )][@stdlib/assert/is-same-float32array]: test if two arguments are both Float32Arrays and have the same values.
• [isSameFloat64Array( v1, v2 )][@stdlib/assert/is-same-float64array]: test if two arguments are both Float64Arrays and have the same values.
• [isSharedArrayBuffer( value )][@stdlib/assert/is-sharedarraybuffer]: test if a value is a SharedArrayBuffer.
• [isTruthyArray( value )][@stdlib/assert/is-truthy-array]: test if a value is an array-like object containing only truthy values.
• [isTypedArrayLength( value )][@stdlib/assert/is-typed-array-length]: test if a value is a valid typed array length.
• [isTypedArrayLike( value )][@stdlib/assert/is-typed-array-like]: test if a value is typed-array-like.
• [isTypedArray( value )][@stdlib/assert/is-typed-array]: test if a value is a typed array.
• [isUnityProbabilityArray( value )][@stdlib/assert/is-unity-probability-array]: test if a value is an array of probabilities that sum to one.

To test for error objects, the namespace includes the following utilities:

• [isError( value )][@stdlib/assert/is-error]: test if a value is an Error object.
• [isEvalError( value )][@stdlib/assert/is-eval-error]: test if a value is an EvalError object.
• [isRangeError( value )][@stdlib/assert/is-range-error]: test if a value is a RangeError object.
• [isReferenceError( value )][@stdlib/assert/is-reference-error]: test if a value is a ReferenceError object.
• [isSyntaxError( value )][@stdlib/assert/is-syntax-error]: test if a value is a SyntaxError object.
• [isTypeError( value )][@stdlib/assert/is-type-error]: test if a value is a TypeError object.
• [isURIError( value )][@stdlib/assert/is-uri-error]: test if a value is a URIError object.

The namespace exposes the following constants concerning the current running process:

• [IS_BIG_ENDIAN][@stdlib/assert/is-big-endian]: check if an environment is big endian.
• [IS_BROWSER][@stdlib/assert/is-browser]: check if the runtime is a web browser.
• [IS_DARWIN][@stdlib/assert/is-darwin]: boolean indicating if the current process is running on Darwin.
• [IS_DOCKER][@stdlib/assert/is-docker]: check if the process is running in a Docker container.
• [IS_ELECTRON_MAIN][@stdlib/assert/is-electron-main]: check if the runtime is the main Electron process.
• [IS_ELECTRON_RENDERER][@stdlib/assert/is-electron-renderer]: check if the runtime is the Electron renderer process.
• [IS_ELECTRON][@stdlib/assert/is-electron]: check if the runtime is Electron.
• [IS_LITTLE_ENDIAN][@stdlib/assert/is-little-endian]: check if an environment is little endian.
• [IS_MOBILE][@stdlib/assert/is-mobile]: check if the current environment is a mobile device.
• [IS_NODE][@stdlib/assert/is-node]: check if the runtime is Node.js.
• [IS_TOUCH_DEVICE][@stdlib/assert/is-touch-device]: check if the current environment is a touch device.
• [IS_WEB_WORKER][@stdlib/assert/is-web-worker]: check if the runtime is a web worker.
• [IS_WINDOWS][@stdlib/assert/is-windows]: boolean indicating if the current process is running on Windows.

To test whether a runtime environment supports certain features, the namespace includes the following utilities:

• [hasArrayBufferSupport()][@stdlib/assert/has-arraybuffer-support]: detect native ArrayBuffer support.
• [hasArrowFunctionSupport()][@stdlib/assert/has-arrow-function-support]: detect native arrow function support.
• [hasAsyncAwaitSupport()][@stdlib/assert/has-async-await-support]: detect native async/await support.
• [hasAsyncIteratorSymbolSupport()][@stdlib/assert/has-async-iterator-symbol-support]: detect native Symbol.asyncIterator support.
• [hasBigIntSupport()][@stdlib/assert/has-bigint-support]: detect native BigInt support.
• [hasBigInt64ArraySupport()][@stdlib/assert/has-bigint64array-support]: detect native BigInt64Array support.
• [hasBigUint64ArraySupport()][@stdlib/assert/has-biguint64array-support]: detect native BigUint64Array support.
• [hasClassSupport()][@stdlib/assert/has-class-support]: detect native class support.
• [hasDataViewSupport()][@stdlib/assert/has-dataview-support]: detect native DataView support.
• [hasDefinePropertiesSupport()][@stdlib/assert/has-define-properties-support]: detect Object.defineProperties support.
• [hasDefinePropertySupport()][@stdlib/assert/has-define-property-support]: detect Object.defineProperty support.
• [hasFloat32ArraySupport()][@stdlib/assert/has-float32array-support]: detect native Float32Array support.
• [hasFloat64ArraySupport()][@stdlib/assert/has-float64array-support]: detect native Float64Array support.
• [hasFunctionNameSupport()][@stdlib/assert/has-function-name-support]: detect native function name support.
• [hasGeneratorSupport()][@stdlib/assert/has-generator-support]: detect native generator function support.
• [hasGlobalThisSupport()][@stdlib/assert/has-globalthis-support]: detect globalThis support.
• [hasInt16ArraySupport()][@stdlib/assert/has-int16array-support]: detect native Int16Array support.
• [hasInt32ArraySupport()][@stdlib/assert/has-int32array-support]: detect native Int32Array support.
• [hasInt8ArraySupport()][@stdlib/assert/has-int8array-support]: detect native Int8Array support.
• [hasIteratorSymbolSupport()][@stdlib/assert/has-iterator-symbol-support]: detect native Symbol.iterator support.
• [hasMapSupport()][@stdlib/assert/has-map-support]: detect native Map support.
• [hasNodeBufferSupport()][@stdlib/assert/has-node-buffer-support]: detect native Buffer support.
• [hasProxySupport()][@stdlib/assert/has-proxy-support]: detect native Proxy support.
• [hasSetSupport()][@stdlib/assert/has-set-support]: detect native Set support.
• [hasSharedArrayBufferSupport()][@stdlib/assert/has-sharedarraybuffer-support]: detect native SharedArrayBuffer support.
• [hasSymbolSupport()][@stdlib/assert/has-symbol-support]: detect native Symbol support.
• [hasToStringTagSupport()][@stdlib/assert/has-tostringtag-support]: detect native Symbol.toStringTag support.
• [hasUint16ArraySupport()][@stdlib/assert/has-uint16array-support]: detect native Uint16Array support.
• [hasUint32ArraySupport()][@stdlib/assert/has-uint32array-support]: detect native Uint32Array support.
• [hasUint8ArraySupport()][@stdlib/assert/has-uint8array-support]: detect native Uint8Array support.
• [hasUint8ClampedArraySupport()][@stdlib/assert/has-uint8clampedarray-support]: detect native Uint8ClampedArray support.
• [hasWebAssemblySupport()][@stdlib/assert/has-wasm-support]: detect native WebAssembly support.
• [hasWeakMapSupport()][@stdlib/assert/has-weakmap-support]: detect native WeakMap support.
• [hasWeakSetSupport()][@stdlib/assert/has-weakset-support]: detect native WeakSet support.

The remaining namespace utilities are as follows:

• [contains( val, searchValue[, position] )][@stdlib/assert/contains]: test if an array-like value contains a search value.
• [deepEqual( a, b )][@stdlib/assert/deep-equal]: test for deep equality between two values.
• [deepHasOwnProp( value, path[, options] )][@stdlib/assert/deep-has-own-property]: test whether an object contains a nested key path.
• [deepHasProp( value, path[, options] )][@stdlib/assert/deep-has-property]: test whether an object contains a nested key path, either own or inherited.
• [hasOwnProp( value, property )][@stdlib/assert/has-own-property]: test if an object has a specified property.
• [hasProp( value, property )][@stdlib/assert/has-property]: test if an object has a specified property, either own or inherited.
• [hasUTF16SurrogatePairAt( string, position )][@stdlib/assert/has-utf16-surrogate-pair-at]: test if a position in a string marks the start of a UTF-16 surrogate pair.
• [instanceOf( value, constructor )][@stdlib/assert/instance-of]: test whether a value has in its prototype chain a specified constructor as a prototype property.
• [isAbsoluteHttpURI( value )][@stdlib/assert/is-absolute-http-uri]: test whether a value is an absolute HTTP(S) URI.
• [isAbsolutePath( value )][@stdlib/assert/is-absolute-path]: test if a value is an absolute path.
• [isAbsoluteURI( value )][@stdlib/assert/is-absolute-uri]: test whether a value is an absolute URI.
• [isAccessorPropertyIn( value, property )][@stdlib/assert/is-accessor-property-in]: test if an object's own or inherited property has an accessor descriptor.
• [isAccessorProperty( value, property )][@stdlib/assert/is-accessor-property]: test if an object's own property has an accessor descriptor.
• [isAlphagram( value )][@stdlib/assert/is-alphagram]: test if a value is an alphagram.
• [isAlphaNumeric( value )][@stdlib/assert/is-alphanumeric]: test whether a string contains only alphanumeric characters.
• [isAnagram( str, value )][@stdlib/assert/is-anagram]: test if a value is an anagram.
• [isArguments( value )][@stdlib/assert/is-arguments]: test if a value is an arguments object.
• [isArrowFunction( value )][@stdlib/assert/is-arrow-function]: test if a value is an arrow function.
• [isASCII( value )][@stdlib/assert/is-ascii]: test whether a character belongs to the ASCII character set and whether this is true for all characters in a provided string.
• [isBetween( value, a, b[, left, right] )][@stdlib/assert/is-between]: test if a value is between two values.
• [isBigInt( value )][@stdlib/assert/is-bigint]: test if a value is a BigInt.
• [isBinaryString( value )][@stdlib/assert/is-binary-string]: test if a value is a binary string.
• [isBlankString( value )][@stdlib/assert/is-blank-string]: test if a value is a blank string.
• [isBoxedPrimitive( value )][@stdlib/assert/is-boxed-primitive]: test if a value is a JavaScript boxed primitive.
• [isBuffer( value )][@stdlib/assert/is-buffer]: test if a value is a Buffer object.
• [isCamelcase( value )][@stdlib/assert/is-camelcase]: test if a value is a camelcase string.
• [isCapitalized( value )][@stdlib/assert/is-capitalized]: test if a value is a string having an uppercase first character.
• [isCircular( value )][@stdlib/assert/is-circular]: test if a value is a plain object containing a circular reference.
• [isCircular( value )][@stdlib/assert/is-circular]: test if an object-like value contains a circular reference.
• [isClass( value )][@stdlib/assert/is-class]: test if a value is a class.
• [isCollection( value )][@stdlib/assert/is-collection]: test if a value is a collection.
• [isComposite( value )][@stdlib/assert/is-composite]: test if a value is a composite number.
• [isConfigurablePropertyIn( value, property )][@stdlib/assert/is-configurable-property-in]: test if an object's own or inherited property is configurable.
• [isConfigurableProperty( value, property )][@stdlib/assert/is-configurable-property]: test if an object's own property is configurable.
• [isConstantcase( value )][@stdlib/assert/is-constantcase]: test if a value is a constantcase string.
• [isCurrentYear( value )][@stdlib/assert/is-current-year]: test if a value is the current year.
• [isDataPropertyIn( value, property )][@stdlib/assert/is-data-property-in]: test if an object's own or inherited property has a data descriptor.
• [isDataProperty( value, property )][@stdlib/assert/is-data-property]: test if an object's own property has a data descriptor.
• [isDataView( value )][@stdlib/assert/is-dataview]: test if a value is a DataView.
• [isDigitString( value )][@stdlib/assert/is-digit-string]: test whether a string contains only numeric digits.
• [isDomainName( value )][@stdlib/assert/is-domain-name]: test if a value is a domain name.
• [isDurationString( value )][@stdlib/assert/is-duration-string]: test if a value is a duration string.
• [isEmailAddress( value )][@stdlib/assert/is-email-address]: test if a value is an email address.
• [isEmptyCollection( value )][@stdlib/assert/is-empty-collection]: test if a value is an empty collection.
• [isEmptyObject( value )][@stdlib/assert/is-empty-object]: test if a value is an empty object.
• [isEmptyString( value )][@stdlib/assert/is-empty-string]: test if a value is an empty string.
• [isEnumerablePropertyIn( value, property )][@stdlib/assert/is-enumerable-property-in]: test if an object's own or inherited property is enumerable.
• [isEnumerableProperty( value, property )][@stdlib/assert/is-enumerable-property]: test if an object's own property is enumerable.
• [isEven( value )][@stdlib/assert/is-even]: test if a value is an even number.
• [isFalsy( value )][@stdlib/assert/is-falsy]: test if a value is falsy.
• [isFinite( value )][@stdlib/assert/is-finite]: test if a value is a finite number.
• [isGeneratorObjectLike( value )][@stdlib/assert/is-generator-object-like]: test if a value is generator object-like.
• [isGeneratorObject( value )][@stdlib/assert/is-generator-object]: test if a value is a generator object.
• [isgzipBuffer( value )][@stdlib/assert/is-gzip-buffer]: test if a value is a gzip buffer.
• [isHexString( value )][@stdlib/assert/is-hex-string]: test whether a string contains only hexadecimal digits.
• [isInfinite( value )][@stdlib/assert/is-infinite]: test if a value is an infinite number.
• [isInheritedProperty( value, property )][@stdlib/assert/is-inherited-property]: test if an object has an inherited property.
• [isIterableLike( value )][@stdlib/assert/is-iterable-like]: test if a value is iterable-like.
• [isIteratorLike( value )][@stdlib/assert/is-iterator-like]: test if a value is iterator-like.
• [isJSON( value )][@stdlib/assert/is-json]: test if a value is a parseable JSON string.
• [isKebabcase( value )][@stdlib/assert/is-kebabcase]: test if a value is a string in kebab case.
• [isLeapYear( [value] )][@stdlib/assert/is-leap-year]: test if a value corresponds to a leap year in the Gregorian calendar.
• [isLocalhost( value )][@stdlib/assert/is-localhost]: test whether a value is a localhost hostname.
• [isLowercase( value )][@stdlib/assert/is-lowercase]: test if a value is a lowercase string.
• [isMethodIn( value, property )][@stdlib/assert/is-method-in]: test if an object has a specified method name, either own or inherited.
• [isMethod( value, property )][@stdlib/assert/is-method]: test if an object has a specified method name.
• [isMultiSlice( value )][@stdlib/assert/is-multi-slice]: test if a value is a MultiSlice.
• [isNamedTypedTupleLike( value )][@stdlib/assert/is-named-typed-tuple-like]: test if a value is named typed tuple-like.
• [isNativeFunction( value )][@stdlib/assert/is-native-function]: test if a value is a native function.
• [isNegativeZero( value )][@stdlib/assert/is-negative-zero]: test if a value is a number equal to negative zero.
• [isNodeBuiltin( value )][@stdlib/assert/is-node-builtin]: test whether a string matches a Node.js built-in module name.
• [isNodeDuplexStreamLike( value )][@stdlib/assert/is-node-duplex-stream-like]: test if a value is Node duplex stream-like.
• [isNodeReadableStreamLike( value )][@stdlib/assert/is-node-readable-stream-like]: test if a value is Node readable stream-like.
• [isNodeREPL()][@stdlib/assert/is-node-repl]: check if running in a Node.js REPL environment.
• [isNodeStreamLike( value )][@stdlib/assert/is-node-stream-like]: test if a value is Node stream-like.
• [isNodeTransformStreamLike( value )][@stdlib/assert/is-node-transform-stream-like]: test if a value is Node transform stream-like.
• [isNodeWritableStreamLike( value )][@stdlib/assert/is-node-writable-stream-like]: test if a value is Node writable stream-like.
• [isNonConfigurablePropertyIn( value, property )][@stdlib/assert/is-nonconfigurable-property-in]: test if an object's own or inherited property is non-configurable.
• [isNonConfigurableProperty( value, property )][@stdlib/assert/is-nonconfigurable-property]: test if an object's own property is non-configurable.
• [isNonEnumerablePropertyIn( value, property )][@stdlib/assert/is-nonenumerable-property-in]: test if an object's own or inherited property is non-enumerable.
• [isNonEnumerableProperty( value, property )][@stdlib/assert/is-nonenumerable-property]: test if an object's own property is non-enumerable.
• [isObjectLike( value )][@stdlib/assert/is-object-like]: test if a value is object-like.
• [isOdd( value )][@stdlib/assert/is-odd]: test if a value is an odd number.
• [isPascalcase( value )][@stdlib/assert/is-pascalcase]: test if a value is a string in Pascal case.
• [isPlainObject( value )][@stdlib/assert/is-plain-object]: test if a value is a plain object.
• [isPositiveZero( value )][@stdlib/assert/is-positive-zero]: test if a value is a number equal to positive zero.
• [isPrime( value )][@stdlib/assert/is-prime]: test if a value is a prime number.
• [isPrimitive( value )][@stdlib/assert/is-primitive]: test if a value is a JavaScript primitive.
• [isPRNGLike( value )][@stdlib/assert/is-prng-like]: test if a value is PRNG-like.
• [isProbability( value )][@stdlib/assert/is-probability]: test if a value is a probability.
• [isPropertyKey( value )][@stdlib/assert/is-property-key]: test whether a value is a property key.
• [isPrototypeOf( obj, prototype )][@stdlib/assert/is-prototype-of]: test if an object's prototype chain contains a provided prototype.
• [isReadOnlyPropertyIn( value, property )][@stdlib/assert/is-read-only-property-in]: test if an object's own or inherited property is read-only.
• [isReadOnlyProperty( value, property )][@stdlib/assert/is-read-only-property]: test if an object's own property is read-only.
• [isReadWritePropertyIn( value, property )][@stdlib/assert/is-read-write-property-in]: test if an object's own or inherited property is readable and writable.
• [isReadWriteProperty( value, property )][@stdlib/assert/is-read-write-property]: test if an object's own property is readable and writable.
• [isReadablePropertyIn( value, property )][@stdlib/assert/is-readable-property-in]: test if an object's own or inherited property is readable.
• [isReadableProperty( value, property )][@stdlib/assert/is-readable-property]: test if an object's own property is readable.
• [isRegExpString( value )][@stdlib/assert/is-regexp-string]: test if a value is a regular expression string.
• [isRelativePath( value )][@stdlib/assert/is-relative-path]: test if a value is a relative path.
• [isRelativeURI( value )][@stdlib/assert/is-relative-uri]: test whether a value is a relative URI.
• [isSameComplex128( v1, v2 )][@stdlib/assert/is-same-complex128]: test if two arguments are both double-precision complex floating-point numbers and have the same value.
• [isSameComplex64( v1, v2 )][@stdlib/assert/is-same-complex64]: test if two arguments are both single-precision complex floating-point numbers and have the same value.
• [isSameNativeClass( a, b )][@stdlib/assert/is-same-native-class]: test if two arguments have the same native class.
• [isSameType( a, b )][@stdlib/assert/is-same-type]: test if two arguments have the same type.
• [isSameValueZero( a, b )][@stdlib/assert/is-same-value-zero]: test if two arguments are the same value.
• [isSameValue( a, b )][@stdlib/assert/is-same-value]: test if two arguments are the same value.
• [isSemVer( value )][@stdlib/assert/is-semver]: test if a value is a semantic version string.
• [isSlice( value )][@stdlib/assert/is-slice]