What is the best way to implement a new method in an immutable-js Map?

Question

What is the best way to implement a new method in an immutable-js Map?

I was looking to incorporate a simple debugging method into immutable js for easier debugging purposes...

log(msg) {
  console.log(msg, this.toJS());
  return this;
}

This way, I could simplify the process of debugging chained expressions like:

someImmutableMap
  .toList()
  .slice(index, index + ITEMS_PER_PAGE)
  .filter(index => !!index)
  .log('Filter: ')
  .map(griddleMapper)
  .toJS()

Is there already something similar available? If not, how can I implement it into the Map class in order to submit a pull request?

I attempted to add it to src/Map.js within the Map class definition and created a basic test for it, but the test failed with

Property 'log' does not exist on type 'Map<string, number>'.

I believe that's because I may need to define the type in type-definitions, but as I am unfamiliar with typescript/flow, I'm feeling quite lost.

Here is my forked repository with the changes I've outlined above..

Any assistance would be greatly appreciated.

typescript typescript-typings flowtype immutable.js

Answer 1

Answer №1

One approach to consider is extending the prototype of Collection (the base type) in this manner:

Immutable.Collection.prototype.log = function(msg){
    console.log(msg, this.toJS());
    return this;
};

Alternatively, you could use the es6 class style and relocate your log() method here. However, as pointed out by loganfsmyth earlier, this practice is often discouraged due to potential confusion and compatibility issues.

Another option is creating a helper function like so:

function logImmutable(msg, obj){
    console.log(msg, obj.toJS());
    return obj;
}

In using this function, you would proceed as follows:

logImmutable('Filter', someImmutableMap
    .toList()
    .slice(index, index + ITEMS_PER_PAGE)
    .filter(index => !!index)) // note the extra paren :-P
    .map(griddleMapper)
    .toJS();

Nevertheless, it's worth noting that these approaches may impact developer experience and overall readability.

Yet another solution could involve utilizing a tool such as https://github.com/mattzeunert/immutable-object-formatter-extension, which enhances the standard console.log() functionality for better handling of immutable.js objects.

Answer 2

One approach to consider is extending the prototype of Collection (the base type) in this manner:

Immutable.Collection.prototype.log = function(msg){
    console.log(msg, this.toJS());
    return this;
};

Alternatively, you could use the es6 class style and relocate your log() method here. However, as pointed out by loganfsmyth earlier, this practice is often discouraged due to potential confusion and compatibility issues.

Another option is creating a helper function like so:

function logImmutable(msg, obj){
    console.log(msg, obj.toJS());
    return obj;
}

In using this function, you would proceed as follows:

logImmutable('Filter', someImmutableMap
    .toList()
    .slice(index, index + ITEMS_PER_PAGE)
    .filter(index => !!index)) // note the extra paren :-P
    .map(griddleMapper)
    .toJS();

Nevertheless, it's worth noting that these approaches may impact developer experience and overall readability.

Yet another solution could involve utilizing a tool such as https://github.com/mattzeunert/immutable-object-formatter-extension, which enhances the standard console.log() functionality for better handling of immutable.js objects.

What is the best way to implement a new method in an immutable-js Map?

Answer №1

Similar questions

Challenges with Loading JSON Dynamically in Next.js using an NPM Package

What is the best way to retrieve matching values based on IDs from an imported table?

Utilizing useLocation for Defining Text Styles

Using MatTableDataSource in a different Angular component

Setting up a winston logger in NestJS - A simple guide!

Clicking on an icon to initiate rotation (Material UI)

Angular2 form builder generating dynamic forms based on results of asynchronous calls

Troubleshooting issues with TypeScript D3 v4 module import functionality

Swiping in Angular2 gets a new twist with Swiper typings

I'm having trouble with the calculator, unable to identify the issue (Typescript)

The data returned from the useFetch function is currently unavailable

Exploring the relationships between nested tuple types

Tips for notifying the user about incorrect login credentials in Ionic 3

Troubleshooting font color issues with PrimeNG charts in Angular

Testing Angular Components with Jasmine and Karma: When handling the 'onChange' event, the changeEvent parameter of type MatRadioChange should not be void and must be assigned to a parameter of type

The seamless fusion of Express with Typescript

Calling a typed function with conditional types in Typescript from within another function

Is it possible for a TypeScript interface to inherit from a Function?

Angular Form Validations - input values must not match the initial values

When there are updates in language, a new service request is needed