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Class Methods Inspection Utilities

Powerful utilities for examining and summarizing the instance/static methods of JavaScript/TypeScript classes. Analyze class APIs, count methods, and get comprehensive breakdowns—great for meta-programming, documentation tooling, and runtime validation.

Import​

import {
  getInstanceMethodNames,
  getStaticMethodNames,
  countInstanceMethods,
  countStaticMethods,
  getClassDetails,
} from 'nhb-toolbox';

Quick Overview​

  • getInstanceMethodNames: Lists names of all instance methods declared directly on a class.
  • getStaticMethodNames: Lists static method names declared on the class itself.
  • countInstanceMethods/countStaticMethods: Get instance/static method counts.
  • getClassDetails: Get comprehensive info (names & counts).
  • All return values are sorted alphabetically.

Usage Examples​

class Example {
  constructor() {}
  foo() {}
  bar() {}
  static zap() {}
  static zip() {}
}

API Reference​

getInstanceMethodNames​

function getInstanceMethodNames(cls: Constructor): string[]

Returns the sorted names of all instance methods defined directly on the class prototype (excluding inherited members and the constructor).

ParameterTypeDescription
clsConstructorThe class constructor (not an instance)

getStaticMethodNames​

function getStaticMethodNames(cls: Constructor): string[]

Returns the sorted names of all static methods defined directly on the class (excluding 'prototype', 'name', 'length', etc.).

countInstanceMethods​

function countInstanceMethods(cls: Constructor): number

Returns the count of instance methods (see getInstanceMethodNames).

Alias​

  • getInstanceMethodsCount

countStaticMethods​

function countStaticMethods(cls: Constructor): number

Returns the count of static methods (see getStaticMethodNames).

Alias​

  • getStaticMethodsCount

getClassDetails​

function getClassDetails(cls: Constructor): ClassDetails

Returns a clean summary of a class’s instance/static method names and counts.

Returns​

interface ClassDetails {
  instanceNames: string[]; // List of instance method names
  staticNames: string[];   // List of static method names
  instances: number;       // Number of instance methods
  statics: number;         // Number of static methods
  total: number;           // Total methods (instance + static)
}

Key Features​

  • Alphabetical Sorting: Always get deterministic, sorted lists.
  • Directly Defined Only: Ignores prototype-chain/inherited members.
  • TypeScript Support: Works seamlessly in TS and JS.

Limitations​

  • No Inherited Methods: Only methods defined directly on the class (not the parent) are listed.
  • No Symbol Support: Only string-named methods are included (symbol-named methods are ignored).
  • No Property Types: Does not indicate async/getter/setter/property nature; only whether a key is a method.
  • Building class API documentation tools.
  • Validating shape of user-extended classes.
  • Automatic test-suite coverage reporting for class APIs.
  • Debugging and runtime introspection for advanced libraries.

Conclusion:
These utilities provide developer-friendly introspection of any ES6 class or constructor, helping with reflection, documentation, metaprogramming, and testing. Easy to drop in and reliable for modern JavaScript and TypeScript codebases.