Pull to refresh
1048.17

Programming *

The art of creating computer programs

Show first
Period
Level of difficulty

Details

Reading time6 min
Views1K
How often do you get to 404 pages? Usually, they are not styled and stay default. Recently I’ve found test.do.am which interactive character attracts attention and livens up the error page.

Probably, there was just a cat picture, then they thought up eyes movement and developer implemented the idea.imageNow user visits the page and checks out the effect. It’s cool and pleasant small feature, it catches, then user discusses it with colleagues or friends and even repeats the feature. It could be this easy, if not:

Announcing TypeScript 3.3

Reading time5 min
Views1.1K

If you’re unfamiliar with TypeScript, it’s a language that brings static type-checking to JavaScript so that you can catch issues before you even run your code – or before you even save your file. It also includes the latest JavaScript features from the ECMAScript standard on older browsers and runtimes by compiling those features into a form that they understand. But beyond type-checking and compiling your code, TypeScript also provides tooling in your favorite editor so that you can jump to the definition of any variable, find who’s using a given function, and automate refactorings and fixes to common problems.

Read more →

Announcing F# 4.6 Preview

Reading time10 min
Views1.6K

We’re excited to announce that Visual Studio 2019 will ship a new version of F# when it releases: F# 4.6!


F# 4.6 is a smaller update to the F# language, making it a “true” point-release. As with previous versions of F#, F# 4.6 was developed entirely via an open RFC (requests for comments) process. The F# community has offered very detailed feedback in discussions for this version of the language. You can view all RFCs that correspond with this release here:



This post will detail the feature set and how to get started.

Read more →

Lifetime Profile Update in Visual Studio 2019 Preview 2

Reading time5 min
Views1.4K

The C++ Core Guidelines’ Lifetime Profile, which is part of the C++ Core Guidelines, aims to detect lifetime problems, like dangling pointers and references, in C++ code. It uses the type information already present in the source along with some simple contracts between functions to detect defects at compile time with minimal annotation.



Read more →

SAPUI5 for dummies part 2: A complete step-by-step exercise

Reading time4 min
Views7.5K


Introduction & Recap


In the previous blog post, we started designing our application rendering a table with some Business Partner. We learned what OData protocol is, how to read an OData XML manifest, how to bind data to a Table and how to customize columns layout based on different screen resolution.


What will be covered on this exercise


With Part 2 of this series of blog posts, we will learn how to interact with data in our Tables and List. We will learn how to filter and sort data in a smart way.


  • Create JSONModel to handle local data
  • Set a default sizeLimit to our JSONModel
  • FilterBar: UI control that displays filters in a user-friendly manner to populate values for a query
  • Use XML Fragments to create a View Settings Dialog to handle sort and group data
  • Filter and Sort data
  • Add an Info Toolbar to our table to display useful information
Read more →

[SAP] SAPUI5 for dummies part 1: A complete step-by-step exercise

Reading time2 min
Views4K


Introduction & Recap


In the previous blog post, we have created a new SAPUI5 application on our SAP SCP WebIDE Full stack and we have configured it to use the destination to the SAP Netweaver Gateway Demo ES5.


What will be covered on this exercise


  • What is an XML Metadata Manifest and what’s inside it?
  • How to use our OData Model and bind it into our application
  • Use a sap.m.Table with items and property binding
  • Use sap.ui.model.type.DateTime to format JavaScript Date
  • How to style columns to act differently on mobile/tablet/desktop devices
Read more →

Automation VS Chaos

Reading time5 min
Views1.1K
image

IT technologies evolution allowed to control huge data flows. Business has a lot of IT solutions: CRM, ERP, BPM, accounting systems or at least just Excel and Word. Companies are different too. Some of companies are composed of plenty branches. Let’s name such as “Pyramid”. Pyramids have data synchronization issue for pile of IT systems. Software vendors and versions differ for branches significantly. In addition management company continuously modify reporting requirements that causes frustration assaults in the branches. This is a story about the project I happened to encounter chaos that needed to be systematized and automated. Low budget and tight deadlines limited the use of most existing industrial solutions but opened up scope for creativity.
Читать дальше →

Python Vs R — Data Science

Reading time3 min
Views3.8K
When mulling over the best programming language to use for data science, Python and R ring a bell (very quickly). While there are a lot of languages like C, C++, Java, Julia, Perl, and Scala, it's protected to state that Python and R are the harbingers in data science.

While a great deal of data researchers will discuss the customary shortcomings like data wrangling in R or data representation in Python, ongoing improvements like Altair for Python or R have adequately reacted to these shortcomings.

So which one would it be a good idea for you to decide for your next data investigation venture?

R has been ruling this space for a long time now. This bodes well as this programming language was explicitly intended for analysts.
Read more →

Detecting in C++ whether a type is defined: Predeclaring things you want to probe

Reading time4 min
Views2.7K
Last time, we used SFINAE to detect whether a type had a definition, and we used that in combination with if constexpr and generic lambdas so that code could use the type if it is defined, while still being accepted by the compiler (and being discarded) if the type is not defined.

However, our usage had a few issues, some minor annoyance, some more frustrating.

  • You had to say struct all the time.
  • If the type didn’t exist, the act of naming it caused the type to be injected into the current namespace, not the namespace you expected the type to be in.
  • You must use the struct technique with an unqualified name. You can’t use it to probe a type that you didn’t import into the current namespace.

We can fix all three of the problems with a single solution: Predeclare the type in the desired namespace.

Read more →

The big interview with Martin Kleppmann: “Figuring out the future of distributed data systems”

Reading time25 min
Views2.9K


Dr. Martin Kleppmann is a researcher in distributed systems at the University of Cambridge, and the author of the highly acclaimed «Designing Data-Intensive Applications» (O'Reilly Media, 2017). 

Kevin Scott, CTO at Microsoft once said: «This book should be required reading for software engineers. Designing Data-Intensive Applications is a rare resource that connects theory and practice to help developers make smart decisions as they design and implement data infrastructure and systems.»

Martin’s main research interests include collaboration software, CRDTs, and formal verification of distributed algorithms. Previously he was a software engineer and an entrepreneur at several Internet companies including LinkedIn and Rapportive, where he worked on large-scale data infrastructure.

Vadim Tsesko (@incubos) is a lead software engineer at Odnoklassniki who works in Core Platform team. Vadim’s scientific and engineering interests include distributed systems, data warehouses and verification of software systems.

Contents:


  • Moving from business to academic research;
  • Discussion of «Designing Data-Intensive Applications»;
  • Common sense against artificial hype and aggressive marketing;
  • Pitfalls of CAP theorem and other industry mistakes;
  • Benefits of decentralization;
  • Blockchains, Dat, IPFS, Filecoin, WebRTC;
  • New CRDTs. Formal verification with Isabelle;
  • Event sourcing. Low level approach. XA transactions; 
  • Apache Kafka, PostgreSQL, Memcached, Redis, Elasticsearch;
  • How to apply all that tools to real life;
  • Expected target audience of Martin’s talks and the Hydra conference.

Read more →

How We Find Lambda Expressions in IntelliJ IDEA

Reading time10 min
Views7.4K

Type Hierarchy in IntelliJ IDEACode search and navigation are important features of any IDE. In Java, one of the commonly used search options is searching for all implementations of an interface. This feature is often called Type Hierarchy, and it looks just like the image on the right.


It's inefficient to iterate over all project classes when this feature is invoked. One option is to save the complete class hierarchy in the index during compilation since the compiler builds it anyway. We do this when the compilation is run by the IDE and not delegated, for example, to Gradle. But this works only if nothing has been changed in the module after the compilation. In general, the source code is the most up-to-date information provider, and indexes are based on the source code.


Finding immediate children is a simple task if we are not dealing with a functional interface. When searching for implementations of the Foo interface, we need to find all the classes that have implements Foo and interfaces that have extends Foo, as well as new Foo(...) {...} anonymous classes. To do this, it is enough to build a syntax tree of each project file in advance, find the corresponding constructs, and add them to an index.

Read more →

Visual Studio 2019 .NET productivity

Reading time2 min
Views1.8K

Your friendly neighborhood .NET productivity team (aka. Roslyn) focuses a lot on improving the .NET coding experience. Sometimes it’s the little refactorings and code fixes that really improve your workflow. You may have seen many improvements in the previews, but for all of you who were eagerly awaiting the GA release here’s a few features you may enjoy!


Read more →

What's new in CUBA 7

Reading time11 min
Views1.8K

What's new in CUBA 7


Three years ago we announced the second publicly available major version of the framework. CUBA 6 was the game-changing version — the licensing was turned from proprietary to Apache 2.0. Those days we couldn't even guess where it was going to bring the framework in long term. CUBA community started to grow exponentially, so we have learned a lot of possible (and sometimes impossible) ways of how developers use the framework. Now we are happy to announce CUBA 7, which, we hope, will make development more coherent and joyful for all community members from those just starting their journey in CUBA and Java to skilled enterprise developers and Java experts.


cuba

Read more →

The Links Theory 0.0.2

Level of difficultyMedium
Reading time27 min
Views1.8K

This world needs a new theory — a theory that could describe all the theories on the planet. A theory that could easily describe philosophy, mathematics, physics, and psychology. The one that makes all kinds of sciences computable.

This is exactly what we are working on. If we succeed, this theory will become the unified meta-theory of everything.

A year has passed since our last publication, and our task is to share the progress with our English-speaking audience. This is still not a stable version; it’s a draft. Therefore, we welcome any feedback, as well as your participation in the development of the links theory.

As with everything we have done before, the links theory is published and released into the public domain — it belongs to humanity, that means, it is yours. This work has many authors, but the work itself is far more important than any specific authorship. We hope that today it can become useful to more people.

We invite you to become a part of this exciting adventure.

Witness the birth of meta-theory

OOX 2.0: Out of order execution made easy

Reading time13 min
Views2.3K

As Intel Threading Building Blocks (TBB) is being refreshed using new C++ standard, deprecating tbb::task interface, the need for high-level tasking interface becomes more obvious. In this article, I’m proposing yet another way of defining what a high-level parallel task programming model can look like in modern C++. I created it in 2014 and it was my last contribution to TBB project as its core developer after 9 wonderful years of working there. However, this proposal has not been used in production yet, so a new discussion might help it to be adopted.

Read more

Quick reference of C++ value categories: Part 1

Reading time13 min
Views7.6K

image

The goal of this quick reference is to collect in one place and organize information about value categories in C++, assignment, parameter passing and returning from functions. I tried to make this quick reference convenient to quickly compare and select one of solutions possible, this is why I made several tables here.


For introduction to the topic, please use the following links:


C++ rvalue references and move semantics for beginners
Rvalues redefined
C++ moves for people who don’t know or care what rvalues are
Scott Meyers. Effective Modern C++. 2015
Understanding Move Semantics and Perfect Forwarding: Part 1
Understanding Move Semantics and Perfect Forwarding: Part 2
Understanding Move Semantics and Perfect Forwarding: Part 3
Do we need move and copy assignment

Read more →

Checklist for writing great Visual Studio extensions

Reading time3 min
Views1.1K
Great Visual Studio extensions share a few key features that sets them apart from the rest. They look and feel well crafted, are performant and reliable, do what they advertise to perfection, and blend in naturally among Visual Studio’s own features.

To make it easier to write great extensions, we’ve worked with the extensibility community to come up with a simple checklist to follow. There’s even a GitHub issue template you can use so you remember to go through the checklist.

Read more →

A declarative data-processing pipeline on top of actors? Why not?

Reading time21 min
Views2.7K

Some time ago, in a discussion on one of SObjectizer's releases, we were asked: "Is it possible to make a DSL to describe a data-processing pipeline?" In other words, is it possible to write something like that:


A | B | C | D


and get a working pipeline where messages are going from A to B, and then to C, and then to D. With control that B receives exactly that type that A returns. And C receives exactly that type that B returns. And so on.


It was an interesting task with a surprisingly simple solution. For example, that's how the creation of a pipeline can look like:


auto pipeline = make_pipeline(env, stage(A) | stage(B) | stage(C) | stage(D));

Or, in a more complex case (that will be discussed below):


auto pipeline = make_pipeline( sobj.environment(),
        stage(validation) | stage(conversion) | broadcast(
            stage(archiving),
            stage(distribution),
            stage(range_checking) | stage(alarm_detector{}) | broadcast(
                stage(alarm_initiator),
                stage( []( const alarm_detected & v ) {
                        alarm_distribution( cerr, v );
                    } )
                )
            ) );

In this article, we'll speak about the implementation of such pipeline DSL. We'll discuss mostly parts related to stage(), broadcast() and operator|() functions with several examples of usage of C++ templates. So I hope it will be interesting even for readers who don't know about SObjectizer (if you never heard of SObjectizer here is an overview of this tool).

Read more →

Let's help QueryProvider deal with interpolated strings

Reading time5 min
Views1.7K

Specifics of QueryProvider


QueryProvider can’t deal with this:


var result = _context.Humans
                      .Select(x => $"Name: {x.Name}  Age: {x.Age}")
                      .Where(x => x != "")
                      .ToList();

It can’t deal with any sentence using an interpolated string, but it’ll easily deal with this:


var result = _context.Humans
                      .Select(x => "Name " +  x.Name + " Age " + x.Age)
                      .Where(x => x != "")
                      .ToList();

The most painful thing is to fix bugs after turning on ClientEvaluation (exception for client-side calculation), since all Automapper profiles should be strictly analyzed for interpolation. Let’s find out what’s what and propose our solution to the problem.

Read more →