A C++ container which keeps insertion order

C++ is a poorly designed programming language, and I live a love-hate relatioship with it.

On my vacation days, when working on WinLamb for the next version of SRTEd, I needed a container to keep track of the order the elements were inserted. Among the many useless obscure things that C++ has, it doesn’t have such a container. So I had to write one, which after much struggle I named it the insert_order_map.

Usage example, including iterator support for C++11 range-based for loop:

insert_order_map<wstring, wstring> all = {
  { L"initial", L"blab" },
  { L"initial2", L"bleb" }
};

all[L"first"] = L"abcdef";
all[L"second"] = L"123456";

for (insert_order_map<wstring, wstring>::entry& e : all) {
  wstring key = e.key;
  wstring val = e.value;
}

At first I wondered about using a sentinel linear search, line the one used within store. But then I realized that 99% of the time I’ll be using a string as the key with few elements inserted, thus the initial copy of the string at each search would take away the performance gains of the sentinel algorithm. So I decided to stick to an ordinary linear search.

Avast antivirus sucks

Last month, after having had enough of Avira antivirus intrusive ads popping on my screen all day, I removed it and installed Avast. Then I started seeing my whole trusty Windows 7 x64 going slow, mainly when switching between processes, but until then I blamed the almost 8 years old computer.

That was until yesterday, while debugging C++ in Visual Studio, when I noticed an Avast DLL being loaded in the console. What the hell? It seems that Avast was somewhat injecting its DLL everywhere, making everything go slow. I immediately uninstalled Avast, and instantly my computer became fast as before.

So far I’m running no antivirus program, and I’m in doubt if I really need one. It feels a bit insecure, but at the same time so... fresh.

GitHub markdown style on Visual Studio Code

These days I found out the very useful feature on Visual Studio Code for markdown editing, which renders the MD file on VSCode itself, opening a new tab at right.

However, the rendered markdown styles matches VSCode itself. Since I mainly use markdown on GitHub, I’d like to preview the markdown using GitHub style. So I inspected GitHub and made a quick CSS file to VSCode:

Save the file and add this entry to VSCode user settings, which on Linux looks like this:

"markdown.styles": ["/home/your_name/.config/Code/User/eu-markdown.css"]

The markdown preview should be pretty close to GitHub styling now.

React Material-UI: a FAB with an optional tooltip

I’m using Material UI library to have Material Design components on a rather complex React project. Despite being good, this library unfortunately doesn’t provide a tooltip option to the Float Action Button, something I need at the moment.

I found some useful information on this project issue, and after digging into the code of IconButton – which has a tooltip option – and Tooltip itself, I wrote a component that provides a Float Action Button with an optional tooltip:

The icon is ready to be used with Font Awesome project, which is what I’m using. Other minor adjustments I made, like font size, can just be removed too. And my project requirements are web only, so that’s all I tested.

Extending native objects in create-react-app

Despite being considered a bad practice by some, I like to extend native objects to add some syntatic sugar. However, when working in a React project with create-react-app, I receive the following ESLint error:

Array prototype is read only, properties should not be added  no-extend-native

Fortunately this warning can be disabled by adding a comment in the file where you extend the native object. Putting it all together, this is what I’ve got:

/*eslint no-extend-native: ["error", { "exceptions": ["Array"] }]*/
Object.defineProperty(Array.prototype, 'last', {
  get: function() {
    return this[this.length - 1];
  }
});
Object.defineProperty(Array.prototype, 'empty', {
  get: function() {
    return this.length === 0;
  }
});

Syntatic sugar added, clear console.

Absolute imports with create-react-app

When developing React using create-react-app with custom-react-scripts, I wanted to use absolute paths for import, and I found this: just adding NODE_PATH=src/ to “.env” file. It worked on Windows, but not on Linux.

After a while, I sorted it out: echo $NODE_PATH told me that my Linux had NODE_PATH being set somewhere. Then, being conservative, I just added unset NODE_PATH to “~/.bashrc” file, and it finally worked.

JavaScript development is a nightmare these days.

Google Chrome 61 slow, how to fix

After updating to Chrome 61, I instantly noticed that YouTube became slow, and Google Maps – particularly Street View – became so slow it’s unusable. I went back to Firefox Developer 57, but then I missed Chrome’s search capabilities.

I found out that the problem is the HTML5 canvas, and the fix is rather easy: just disable this flag in Chrome flag page:

chrome://flags/#enable-color-correct-rendering

Instantly all the sites became responsive again.

Grep and find aliases

Two quick bash functions to speed up name and content search on files. These are to be appended at ~/.bashrc file:

function gr { clear ; grep -rn $1 . ; }
function ff { clear ; find . -name "$1" ; }

Holy Grail CSS layout with overflow

This morning – yep, a Sunday morning – I needed to implement an HTML page with the Holy Grail layout. A quick search gave me dozens of implementations, but all of them broke apart when you trew a lot of content into the sections. Being fond of the Flexbox model, I quickly came with an implementation that had all the needed overflow control:

This implementation is also modular: if you don’t need any of the panels, just remove them – the layout will stay working. Also, the satellite panels can have fixed dimensions, see the commented values for width and height.

The funny part is that min-height: 0. It’s there for Firefox; without it, the overflow goes wild. Other interesting thing is the absence of the height: 100% to html and body elements, it’s not needed.

Disabling the useless npm package-lock.json

Recently I’ve updated npm to version 5 while working in one of my projects. Much to my dismay, a “package-lock.json” file started to appear, and I finally understood why I’ve seen this file commited in some projects lately.

But since this feature is basically a horrible idea, I started searching a way to permanently disable it. It looks like I’m not the only one who dislikes this, because I found this excellent post, which points to the solution:

npm set package-lock false

And any more “package-lock.json” files that appear in front of me will be summarily deleted.

Visual Studio Code settings

This morning I was setting up Visual Studio Code at a Lubuntu virtual machine, and after saving the keyboard shortcuts, I opened my current editor to get the settings. Since some of them I consider essential, I decided to publish them here, for further reference.

Simple minimalist JavaScript metronome

These days, when practicing guitar, I needed a metronome. Whey you type “metronome” on Google Search, it actually brings out a functional metronome – however it has no keyboard shortcut keys. So I decided to write a simple metronome, with keyboard keys, from scratch, to suit my needs.

Knowing the imprecision of JavaScript’s setTimeout function, I implemented a timer that adjusts itself each call, thus having a fairly reliable precision.

The code is so simple I decided not to create a GitHub repository, so I’m just sharing the whole source code here: