JS – Mastering Browser Console: Creating a Dynamic Login Form with Declarative Programming

The browser console is typically utilized by most developers just for output information, using functions like console.log(), console.warn(), or console.error(). However, the browser console is interactive and can assist us in many situation if we know how to interact with that.

Normally when we use some console environment to perform some programming, it is most likely to adopt the Declarative Programming paradigm, which we want to receive the result, the output of a certain function after every instruction, and it differs from the Imperative Programming, which we previously define a set of instructions which control the flow of the code execution.

Basically from the browser console we can input and execute JS instructions in the same way we do when we programming in JS using .js files or add code inside <script> tags. However, the benefit of using the console is that we can interact with the JS objects in the exact point of interest, then, we can read or write over the objects state and interact with them, seen the consequences. It could be very useful for analysing complex scenarios .

And moreover, one most nice feature of browser JS console is that it allow us to interact with DOM objects, it means we can interact with every object that is available in the screen, updating their attributes right after every instruction.

This possibilities aligned with the nice environment the browser provide to us, with autocomplete and printing features can be a powerful tool in your daily programming.

 

You can see a demonstration about how to use the browser console at this video:

 


 

You can download the how source code of this example here:

 https://github.com/rafaelqg/code/blob/main/js_browser_console.html

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