Category: Javascript

My Blog. Full Stack Software Engineer. Ex-Growth Hacker.

eval() function javascript, what to use instead

What’s the deal with the eval() function in Javascript?

I can across the eval function today when looking for an alternative to a multiple, nested if statement. This if statement would check what a certain key’s title was and invoke the function which  corresponded to that key name. We thought about listing this out as key value pairs (with the function as the value) in…
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error handling Javascript

Gotchas of error handling and testing, Javascript

Recently I have been mainly working with Node JS and have been tripped up by a few things while trying to handle errors. I noticed other people were also experiencing some problems handling errors and unit testing them correctly. I thought I would make this post in case there are others out there struggling through…
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Live Element Lists vs Static Ones, Why document.getElementsByClassName is different to document.querySelector(‘.className’) : Bitesize JS

Bitesize Javascript series I was working on a bug in our code base with a colleague, when he noticed something strange about the behaviour of document.getElementsByClassName. In our code base it had been implemented as if it acted like document.querySelector, ie. you could save a list of elements to a variable, then mess with those…
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html element root element

Document.documentElement: BiteSize JS and web performance

I was recently advised to use Document.documentElement when querying the DOM to get the html element. This came about because I was refactoring an old code base to swop JQuery for vanilla JS. Doing this I saw: $(‘html’) This is JQueries way of selecting the whole Html element. Since I am relatively new to javascript…
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The future of google's AMP technology. Javascript off the main thread?

The Future of AMP : JavaScript which doesn’t block the main thread?

At ComparetheMarket.com we are constantly optimising the speed of our site. We were an early adaptor of Google’s AMP technology, sold on the mobile page speed win’s it promised. Due to how early we were in using this technology we have faced many challenges on the way. I wanted to look at if the future…
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learning javascript eventloop

Events, EventListeners and their relation to JavaScript, the Browser and the DOM

  Notes on things I have learnt about events and their listeners and JS while working through Wes Bos’s JS30 and talking to colleague at Compare the market. (Beware this is not a coherent article just random scribbles which i took down through a conversation). Events/ Events/ Events The DOM Is an event based system. The…
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