Keynote: Destroy All Memory Corruption

Walter Bright
Nov 21, 14:00 UTC

Slides (PDF) Video Q & A

Memory corruption is a pernicious and expensive problem. Too often scrubbing it out of code requires manual review, which becomes increasingly impractical as the size of code increases. Runtime checks are inadequate because they cannot prove that memory corruption cannot happen since only the test cases are checked. The idea is to be able to detect memory corruption at compile time as much as possible.

D has had great success at greatly reducing many common forms of memory corruption, such as buffer overflows, use of uninitialized pointers, constructing invalid pointers, and dangling pointers into expired stack frames.

The largest remaining category of such problems is tracking the lifetimes of memory objects and the references to them. The idea is to pair every memory allocation with exactly one deallocation and prevent references to a memory object from surviving past the lifetime of that object. This presentation describes the design of a memory ownership and borrowing system suitable for inclusion into the D language, addressing that category.

Walter Bright is the creator and first implementer of the D programming language and has implemented compilers for several other languages. He's an expert in all areas of compiler technology, including front ends, optimizers, code generation, interpreter engines and runtime libraries. Walter regularly writes articles about compilers and programming, is known for engaging and informative presentations, and provides training in compiler development techniques. Many are surprised to discover that Walter is also the creator of the wargame Empire, which is still popular today over 30 years after its debut.

Helpful D Techniques

Ali Çehreli
Nov 21, 14:45 UTC

Slides (PDF) Video Q & A

Loosely related to his DConf 2019 presentation, Ali will present features of D that have proven to be productive at Mercedes-Benz Research and Development, North America: Parallelism, message passing concurrency, nested functions, formatted strings, parsing files at compile-time, profiling and reducing memory allocations, and more.

Ali is a software engineer with programming language experience mostly in C, C++, and D. His past work includes a fun stint at WekaIO, a high performance storage company that bases its technology entirely on D. Ali is the author of the book Programming in D, the Secretary of the D Language Foundation Committee, former acting president of the Silicon Valley Chapter of the ACCU, an organizer of the Silicon Valley DLang meetup group, and a team member of the revolutionary Mill CPU. He currently works in the sensor fusion team of the Autonomous Driving division at Mercedes-Benz Research and Development, North America. One of his responsibilities is helping with ISO 26262 software safety issues.

D: The Functional Programming Language Nobody is Talking About

Robert Schadek
Nov 21, 16:00 UTC

Slides (PDF) Video Q & A

D is a functional programming language, but nobody is talking about it. This should change, as functional programming offers many advances that are easily exploited in D.

D is a multi-paradigm programming language, and one of those paradigms is functional programming. Even though functional programming is often considered to be a niche paradigm, it offers many advantages. These advantages are easily exploited in D. Unfortunately, functional programs are not bug free either, but D's unique combination of built-in unit tests, functional programming, and built-in code coverage allows many/most bugs to be caught early.

Robert Schadek received a master's degree in computer science at the University of Oldenburg. His master's thesis was titled “DMCD A Distributed Multithreading Caching D Compiler” and introduced multi-threading, among other optimizations, to the compiler control flow. He was a computer science PhD student from 2012–2018 at the University of Oldenburg. His PhD research focused on quorum systems in combination with graphs. Since 2018 he has been happily using D in his day job working for Symmetry Investments.

sil-cling: A Story of Three Languages

Alexandru Militaru
Nov 22, 17:15 UTC

Slides (PPTX) Video Q & A

Symmetry Integration Language (SIL) is a D-based domain-specific language of functional flavor. Heavily relying on D's reflection mechanism and its inherent plasticity, one of SIL's greatest achievements is its interoperability with many other sorts of languages and systems. This talk aims to present one of SIL’s extensions, called “sil-cling”, that allows transparent calling of C++ libraries via JIT compilation at runtime. Following DConf’s lightning talks tradition, this presentation will be a quick mix of description and demonstration of sil-cling’s power.

Alexandru Militaru is an MSc student at University "Politehnica" of Bucharest. He is passionate about operating systems and compilers. In his bachelor thesis project, he used D to strengthen the security of Linux kernel modules. This was the subject of his very first talk at DConf 2019. He now works as a D consultant/programmer for Symmetry Investments.

Livestream: Ask Us Anything!

Walter Bright and Átila Neves
Nov 21, 18:00 UTC

Video

DConf wouldn't be DConf, online or otherwise, without the “Ask Us Anything!” tradition, where the language maintainers step onto the stage to face the assembled mob crowd, take their grilling questions, and provide them with the answers they're looking for.

For our online version, Walter and Átila will be taking most questions from the livestream chat, but we'll also invite a limited number of participants into the conference call to ask their questions directly. Details will be provided at the top of the event.

So prepare your statements and compile your queries! Walter and Átila are very much looking forward to them. Really. No fooling.

Parameter Passing & Delegate Covariance: What's Cooking?

Mathias Lang
Nov 21, 19:15 UTC

Slides (PDF) Video Q & A

In this talk, Mathias will share his recent work and future plans related to two topics that are core to D.

First and foremost, parameter passing: how the current defaults affect us and the issues they bring. This includes the recently added `-preview=in`, an experimental feature that landed in D v2.094.0, and which attempts to redefine input parameters.

The second part will focus on an issue that every library developer should be familiar with: how delegates and attributes are often at odds, and how writing good library code to support them is not currently possible. Finally, Mathias will show how a simple language addition could help solve this problem.

Mathias Lang started his journey with D in 2012 while looking for a language which could quench his metaprogramming thirst. After a few years at Sociomantic Labs, he is now CTO for https://bosagora.io, developing a blockchain project in D.

Livecoding Session

Adam D. Ruppe
Nov 21, 20:30 UTC

Video

Adam will demonstrate some of his arsd D libraries as well as his personal development process by livecoding a small, simple, online multiplayer game that runs natively on Windows, Linux, and WebAssembly from the same source, along with a web server to coordinate online play. He'll add functions to the WebAssembly libraries as needed, giving a chance to discuss how and why it works the way it does.

Adam has been a D user for over thirteen years, known as a frequent participant in D chats, the primary creator of the arsd all-purpose library collection, and the author of the D Cookbook.

Keynote: We're not crazy, we promise!

Átila Neves
Nov 22, 14:00 UTC

Slides (PDF) Video Q & A

The trials and tribulations of a programming language designer.

Átila gives some background on his view of programming language design and how he spends his time. He has organized his thoughts into four main topics: why he and Walter care about @safe, his belief in the "less is more" principle, the projects he'd like to be working on, and the projects he's actually working on.

Átila Neves has a PhD in Particle Physics for research done at CERN. Most of the time spent there required programming in C++, with a two-year stint as a Perl programmer on the IT department's security team. He also worked for Cisco for almost seven years, developing networking software in C and C++ and leading his teams in the areas of software quality and testing. He now works as a D consultant/programmer for Symmetry Investments, as well as being the deputy maintainer of the D programming language. He spends his spare time yelling at the screen in frustration while waiting for computers to compile his code.

‘Serialized’: Cleanly Encode/Decode JSON and XML to any Data Type

Mathis Beer
Nov 22, 15:15 UTC

Slides (ODP) Video Q & A

‘Serialized’ is Funkwerk's recently open-sourced library for generically encoding/decoding XML and JSON. This talk is about how to use it, how it looks in practice, leaf encoding/decoding, why XML sucks, generic transformers (functions that take internal data types and yield a simpler data type that can be chained), and a call to action.

Mathis has been working at Funkwerk for over three years. He is the author of Serialized as well as the company's Boilerplate library. He presented at DConf 2019 in London. Mathis is also known in the D community as “FeepingCreature”.

Exposing a D Library to Python Through a C API

Ali Çehreli
Nov 22, 16:45 UTC

Slides (PDF) Video Q & A

This talk will demonstrate a method of exposing a D library through a C API and give an example of using the library from Python.

Ali is a software engineer with programming language experiences mostly in C, C++, and D. His past work includes a fun stint at WekaIO, a high performance storage company that bases its technology entirely on D. Ali is the author of the book Programming in D, the secretary and board member of The D Language Foundation, former acting president of the Silicon Valley Chapter of the ACCU, an organizer of the Silicon Valley DLang meetup group, and a team member of the revolutionary Mill CPU. He currently works in the sensor fusion team of the Autonomous Driving division at Mercedes-Benz Research and Development, North America. One of his responsibilities is helping with ISO 26262 software safety issues.

Trust Me: An Exploration of @trusted Code in D

Steven Schveighoffer
Nov 22, 18:00 UTC

Slides (PDF) Video Q & A

This is a talk for all D coders who care about @safe and @trusted code (which should be all D coders!). Steve will go over memory safety and how D's related attributes can be used, with a focus on the interaction between @safe and @trusted. It's actually easy to write code that's tagged @safe that isn't actually memory safe, thanks to the possibility that @safe and @trusted code can be written with different semantic expectations on the same data. Steve will dig into this through the example of a tagged union implementation.

Steven Schveighoffer has been to every real-world DConf since 2013 and has presented at four of them. He has published an article on the D Blog about writing @trusted code, migrated a very unsafe, complex codebase to be @safe, and worked on fixing @trusted issues in Phobos (D's standard library) and DRuntime.

Faster Compile Times: Approaching Zero Template Overhead

Stefan Koch
Nov 22, 19:15 UTC

Slides (ODP) Video Q & A

The D programming language offers a plethora of compile-time features which allow for metaprogramming and code generation, and which have seen increased usage over time. As a side effect, D programmers who use these features have found themselves facing increased compile times.

In this talk, Stefan will dig into DMD's internals to provide context on this phenomenon. Through code examples, he'll show what can cause increased compile times and how to make them faster. He'll preview work that's currently being done to improve the situation and discuss future directions.

Stefan has been programming in D personally and professionally since 2013. He has taken a special interest in the performance of D’s compile-time features and has been contibuting to DMD for over four years. He has presented either a full talk or a lightning talk at three DConfs and is currently employed as a D programmer by Symmetry Investments.