938 packages found
Get the native type of a value.
type-check allows you to check the types of JavaScript values at runtime with a Haskell like type syntax.
Check if something is a Node.js stream
Check if a value is a plain object
Returns true if a number or string value is a finite number. Useful for regex matches, parsing, user input, etc.
Returns true if an object was created by the `Object` constructor, or Object.create(null).
A little library for asserting types and values.
- type
- types
- type-check
- type-checking
- duck-typing
- arguments
- parameters
- values
- data
- contract
- assert
- check
- verify
- safe
Returns true if the value is an object and not an array or null.
Check if a path is a file, directory, or symlink
Infer the content-type of a request.
Returns true if a value exists, false if empty. Works with deeply nested values using object paths.
Function argument validation for humans
- type
- types
- check
- checking
- guard
- guards
- assert
- assertion
- predicate
- predicates
- is
- validate
- validation
- utility
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Detect the file type of a Buffer/Uint8Array/ArrayBuffer
unist utility to check if a node passes a test
Returns true if a value has the characteristics of a valid JavaScript accessor descriptor.
Returns true if a value has the characteristics of a valid JavaScript data descriptor.
Type check values
Returns true if a value has the characteristics of a valid JavaScript descriptor. Works for data descriptors and accessor descriptors.
A type checking library where each exported function returns either true or false and does not throw. Also added tests.
Test if a double-precision floating-point numeric value is NaN.
- stdlib
- stdmath
- assertion
- assert
- utilities
- utility
- utils
- util
- math
- mathematics
- ieee754
- floating-point
- float
- number
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