Solving data type problems in Ruby or Make data reliable again

 3r3404. 3r3-31. In this article, I would like to talk about what problems with data types exist in Ruby, what problems I encountered, how they can be solved and how to make the data we work with can be relied upon.
 3r3404.
 3r3404. Solving data type problems in Ruby or Make data reliable again
 3r3404. helps to verify this. Rollbar research. where they analyzed more than 1000 Rail applications and identified the most common errors. And 2 out of 10 most frequent errors are connected with the fact that the object cannot respond to a specific message. And therefore, checking the behavior of an object, what duck typing gives us, in many cases may not be enough.
 3r3404.
 3r3404. We...
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When TypeScript exceeds JavaScript in speed tests

 
3r3-31. I am writing this post in response to this where different performance tests are compared, including the same algorithms written in TypeScript and jаvascript. As is known to many, the first when released is translated into the second. TypeScript does not have native support in browsers, it does not have its own engine. Moreover, many of the buns of this language are discarded during transpiling to get pure JS, which can be run in all browsers (if you want, even in Explorer). Good. And now look at the picture. 3r388.  
3r388.  
When TypeScript exceeds JavaScript in speed tests ...
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We write trading robots using the StockSharp graphic framework. Part 2

We write trading robots using the StockSharp graphic framework. Part 2 3r33942. 3r3393955.  3r33965. 3r3393955.  3r33965. We continue to talk about creating trading robots using the platform. StockSharp . In The first material it was about creating a project and drawing the main elements of the trading system. In the final material of the cycle, we will deal directly with the implementation of a trading strategy.
3r3393955.  3r33965. 3r3393955.  3r33965.

Creating a panel of portfolios

3r3393955.  3r33965. By analogy with the toolbar, create a log panel. To do this, add another UserControl to the XAML folder. Give it the name PortfolioGridControl...[/h]
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Work with a database from the application

 3r33400. 3r3-31. 3r33383. In the beginning I will identify some of the problems and features when working with the database, show the holes in the abstractions. Next, we will examine a simpler abstraction based on immutability. 3r33333. 3r33381.  3r33400. 3r33383. It is assumed that the reader is somewhat familiar with the patterns Active Record , Data Maper , Identity Map and Unit of Work . 3r33333. 3r33381.  3r33400. 3r33383. Problems and solutions are considered in the context of sufficiently large projects ...
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Some dictionary internals in CPython (and PyPy)

Some dictionary internals in CPython (and PyPy) 3r3407. 3r3-31. The internal structure of dictionaries in Python is not limited to bucket and closed hashing alone. This is an amazing world of shared keys, caching hashes, DKIX_DUMMY and quick comparisons that can be made even faster (at the cost of a bug with an approximate probability of 2 ^ -64).
 3r3407.
 3r3407. If you don’t know the number of elements in the newly created dictionary, how much memory is spent on each element, why now (CPython 3.6 and later) the dictionary is implemented with two arrays and how does this relate to maintaining the insertion order, or simply didn’t watch the ...
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Oracle Bitmap Index Techniques

Oracle Bitmap Index Techniques 3r3196. 3r3-31. And again, good evening! 3r3181.  3r3196. 3r3181.  3r3196. We start the second stream of our new course 3r336. "Relational DBMS" 3r3184. which we did a little bit after the first run: additional classes on MySQL and Postgres clusters, docker was in demand, and various “file improvements”. So wait for open lessons (in which part of old topics have been carried out) and interesting materials. Today we delve into the techniques of Oracle. 3r3181.  3r3196. 3r3181.  3r3196. Go. 3r3181.  3r3196. 3r3181.  3r3196. Oracle Bitmap indices are very different from standard B-tree indices. In ...
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Virtual memory in ARMv7

Virtual memory in ARMv7Hello!
 
 
The article provides an overview of the virtual memory system architecture ARMv7.
 
 
Headline spoiler [/b]
It does not consider the subtleties of caching, DMA, LPAE and the like. For a more detailed description, refer to the literature at the end of the article.
 
 
 
[h2] The introduction of 3r-3262.
 
The virtual memory system performs several tasks. First, it allows you to place user processes in separate, isolated from each other, memory spaces. This allows you to increase the reliability of the system, the errors of one process do not affect the operation of other processes. Secondly...
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From aircraft to programmers in one year, or how to become a Jedi

From aircraft to programmers in one year, or how to become a Jedi 3r3196. 3r3-31. 3r3179. 3r33180. Yoda: Master Qui-Gon, is there anything else to say to you? 3r3181.  3r3196. Qui-Gon Jin: With your permission, Master. I found the point of concentration of the Great Force. 3r3181.  3r3196. Yoda: Concentration, you said? 3r3181.  3r3196. Mace Windu: Inside a living being? 3r3181.  3r3196. Qui-Gon Jin: In the boy. His cells contain the highest level of midichlorians from all that I have seen. He was probably conceived by midichlorians. 3r3181.  3r3196. Mace Windu: You are hinting at a prophecy about the Chosen One that will bring balance to the Force. Do you believe ...
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Apple Metal in MAPS.ME

Apple Metal in MAPS.ME Hello! 3r3662.  
3r3662.  
In the world there are a huge number of applications on OpenGL, and it seems that Apple is not quite agree with this. Starting with iOS 12 and MacOS Mojave, OpenGL has been rendered obsolete. We integrated Apple Metal into MAPS.ME and are ready to share our experience and results. We will tell how our graphic engine refactored, what difficulties we had to face and, most importantly, how many FPS we have now. 3r3662.  
3r3662.  
Anyone who is interested or is thinking about adding support for Apple Metal in the graphics engine, we invite under the cat. 3r3662.  
...
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Why should marketers learn programming

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