Let’s figure it out by exploring the source code of major Node.js-based projects
It is convenient to organize code into a logical hierarchy of nested folders. A bigger task often can be decomposed into several nested smaller subtasks. The smallest discrete subtasks can be encoded in individual modules. …
Using native absolute modules specifiers relative to the package root instead of double dots, transpilers or bundlers
I am payed for the task completion, not for the hours I play. Unless you are a consultant, you are in the same situation. To complete the task, such as migration of something to something else, I need to create an auxiliary Node.js-based command-line tool that is unlikely to be…
By default open source Shiny server does not pass the request headers to R scripts.
What is Shiny and how request headers could be useful I explained in my previous post. If you need to access request headers in a Shiny application you have two options:
- to buy Shiny Server…
Implementing authentication, authorization and access log in Shiny web applications
Output is the major problem of R. Even compared to Excel, the graphs produced by R are awful. To alleviate the problem of the ugly static output, Shiny package was released. Shiny package displays R output in a browser in…
When virtual DOM makes sense?
Virtual DOM is one of the reasons for using React. In a previous post I demonstrated that React accelerates changes in existing views and does not tangibly slow down rendering of new views. As a sample view I used a page with a table containing 40,000 cells. The cells of…
And also do not annoy users with an infinite scroller.
Browser cannot distinguish invisible from visible contents
Contents shown in a web page usually do not fit into the screen.
When a page is loaded a browser calculates the dimensions and positions of all the displayed elements in the page DOM. …
How to use up a browser’s memory?
When the data set that might interest a single user can fit into a browser memory, it is a good idea to load all the data at once into the browser.
Let’s take clinical data for example. In clinical research scientists work with patient cohorts. In the currently dominating research…
And a critical difference between div tables
There are two reasonable ways to construct a table in a web page:
- using the dedicated
table,tr,thandtdHTML elements - using only
divsbut appropriately styled
The two visually identical tables below are coded using those approaches:
Why 13 characters can occupy megabytes of memory?
In JavaScript, a string length and its size in memory do not always correlate. I mentioned in my previous posts that in JavaScript, depending on their characteristics and origins, strings can be represented as several C++ classes that to save memory and thus CPU time. 1 MB of memory might…
512,000,000 characters long string needs ~1 MB of memory
Max length of a JavaScript string
According to ECMAScript specification a string cannot contain more than 9,007,199,254,740,991 (2⁵³-1) characters. Evidently, the achievable max length also depends on the computer capacity. Also browsers can set their limits. The max string length set in the Chrome source code is 536.8 millions characters. …
