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Assert

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> Assertion utilities.

Installation

``bash npm install @stdlib/assert`

`Usage`

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

#### assert

Namespace providing utilities for data type testing and feature detection.

`javascript 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.

`javascript 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.

`javascript 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 ArrayBuffersupport. - [hasArrowFunctionSupport()][@stdlib/assert/has-arrow-function-support]: detect native arrow functionsupport. - [hasAsyncAwaitSupport()][@stdlib/assert/has-async-await-support]: detect native async/awaitsupport. - [hasAsyncIteratorSymbolSupport()][@stdlib/assert/has-async-iterator-symbol-support]: detect native Symbol.asyncIteratorsupport. - [hasBigIntSupport()][@stdlib/assert/has-bigint-support]: detect native BigIntsupport. - [hasBigInt64ArraySupport()][@stdlib/assert/has-bigint64array-support]: detect native BigInt64Arraysupport. - [hasBigUint64ArraySupport()][@stdlib/assert/has-biguint64array-support]: detect native BigUint64Arraysupport. - [hasClassSupport()][@stdlib/assert/has-class-support]: detect native classsupport. - [hasDataViewSupport()][@stdlib/assert/has-dataview-support]: detect native DataViewsupport. - [hasDefinePropertiesSupport()][@stdlib/assert/has-define-properties-support]: detect Object.definePropertiessupport. - [hasDefinePropertySupport()][@stdlib/assert/has-define-property-support]: detect Object.definePropertysupport. - [hasFloat32ArraySupport()][@stdlib/assert/has-float32array-support]: detect native Float32Arraysupport. - [hasFloat64ArraySupport()][@stdlib/assert/has-float64array-support]: detect native Float64Arraysupport. - [hasFunctionNameSupport()][@stdlib/assert/has-function-name-support]: detect native function namesupport. - [hasGeneratorSupport()][@stdlib/assert/has-generator-support]: detect native generator functionsupport. - [hasGlobalThisSupport()][@stdlib/assert/has-globalthis-support]: detect globalThissupport. - [hasInt16ArraySupport()][@stdlib/assert/has-int16array-support]: detect native Int16Arraysupport. - [hasInt32ArraySupport()][@stdlib/assert/has-int32array-support]: detect native Int32Arraysupport. - [hasInt8ArraySupport()][@stdlib/assert/has-int8array-support]: detect native Int8Arraysupport. - [hasIteratorSymbolSupport()][@stdlib/assert/has-iterator-symbol-support]: detect native Symbol.iteratorsupport. - [hasMapSupport()][@stdlib/assert/has-map-support]: detect native Mapsupport. - [hasNodeBufferSupport()][@stdlib/assert/has-node-buffer-support]: detect native Buffersupport. - [hasProxySupport()][@stdlib/assert/has-proxy-support]: detect native Proxysupport. - [hasSetSupport()][@stdlib/assert/has-set-support]: detect native Setsupport. - [hasSharedArrayBufferSupport()][@stdlib/assert/has-sharedarraybuffer-support]: detect native SharedArrayBuffersupport. - [hasSymbolSupport()][@stdlib/assert/has-symbol-support]: detect native Symbolsupport. - [hasToStringTagSupport()][@stdlib/assert/has-tostringtag-support]: detect native Symbol.toStringTagsupport. - [hasUint16ArraySupport()][@stdlib/assert/has-uint16array-support]: detect native Uint16Arraysupport. - [hasUint32ArraySupport()][@stdlib/assert/has-uint32array-support]: detect native Uint32Arraysupport. - [hasUint8ArraySupport()][@stdlib/assert/has-uint8array-support]: detect native Uint8Arraysupport. - [hasUint8ClampedArraySupport()][@stdlib/assert/has-uint8clampedarray-support]: detect native Uint8ClampedArraysupport. - [hasWebAssemblySupport()][@stdlib/assert/has-wasm-support]: detect native WebAssembly support. - [hasWeakMapSupport()][@stdlib/assert/has-weakmap-support]: detect native WeakMapsupport. - [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 generatorobject-like. - [isGeneratorObject( value )][@stdlib/assert/is-generator-object]: test if a value is a generatorobject. - [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. - [isNonNegativeFinite( value )][@stdlib/assert/is-nonnegative-finite]: test if a value is a number having a nonnegative finite value. - [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. - [isS