Tudor Andrei Cristian Alexandrescu (born 1969) is a
Romanian-American
Romanian Americans () are Americans who have Romanian ancestry. According to the 2023 American Community Survey, 425,738 Americans indicated Romanian as their first or second ancestry, however other sources provide higher estimates, which a ...
programmer
A programmer, computer programmer or coder is an author of computer source code someone with skill in computer programming.
The professional titles Software development, ''software developer'' and Software engineering, ''software engineer' ...
and author. He is particularly known for his pioneering work on policy-based design implemented via
template metaprogramming
Template metaprogramming (TMP) is a metaprogramming technique in which templates are used by a compiler to generate temporary source code, which is merged by the compiler with the rest of the source code and then compiled. The output of these te ...
. These ideas are articulated in his book ''
Modern C++ Design
Modern may refer to:
History
*Modern history
** Early Modern period
** Late Modern period
*** 18th century
*** 19th century
*** 20th century
** Contemporary history
* Moderns, a faction of Freemasonry that existed in the 18th century
Philosophy ...
'' and were first implemented in his programming library,
Loki
Loki is a Æsir, god in Norse mythology. He is the son of Fárbauti (a jötunn) and Laufey (mythology), Laufey (a goddess), and the brother of Helblindi and Býleistr. Loki is married to the goddess Sigyn and they have two sons, Narfi (son of Lo ...
byline
The byline (or by-line in British English) on a newspaper or magazine article gives the name of the writer of the article. Bylines are commonly placed between the headline and the text of the article, although some magazines (notably '' Reader's ...
"Generic".
He became an American citizen in August 2014.
Education and career
Alexandrescu received a B.S. degree in Electrical Engineering from
Polytechnic University of Bucharest
Politehnica University of Bucharest () is a technical university in Bucharest, Romania founded in 1818.
His first article was published in the '' C/C++ Users Journal'' in September 1998. He was a program manager for Netzip, Inc. from April 1999 until February 2000. When the company was acquired by RealNetworks, Inc., he served there as a development manager from February 2000 through September 2001.
Alexandrescu earned a
M.S.
A Master of Science (; abbreviated MS, M.S., MSc, M.Sc., SM, S.M., ScM or Sc.M.) is a master's degree. In contrast to the Master of Arts degree, the Master of Science degree is typically granted for studies in sciences, engineering and medicine ...
(2003) and a
PhD
A Doctor of Philosophy (PhD, DPhil; or ) is a terminal degree that usually denotes the highest level of academic achievement in a given discipline and is awarded following a course of graduate study and original research. The name of the deg ...
(2009) in
computer science
Computer science is the study of computation, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, ...
from the
University of Washington
The University of Washington (UW and informally U-Dub or U Dub) is a public research university in Seattle, Washington, United States. Founded in 1861, the University of Washington is one of the oldest universities on the West Coast of the Uni ...
.
In 2006 Alexandrescu began assisting Walter Bright on the development of the D programming language. He released a book titled ''The D Programming Language'' in May 2010.
From 2010 to 2014, Alexandrescu, Herb Sutter, and
Scott Meyers
Scott Douglas Meyers (born April 9, 1959) is an American author and software consultant, specializing in the C++ computer programming language. He is known for his ''Effective C++'' book series. During his career, he was a frequent speaker at co ...
ran a small annual technical conference called ''C++ and Beyond''.
Alexandrescu worked as a research scientist at
Facebook
Facebook is a social media and social networking service owned by the American technology conglomerate Meta Platforms, Meta. Created in 2004 by Mark Zuckerberg with four other Harvard College students and roommates, Eduardo Saverin, Andre ...
for over 5 years, before departing the company in August 2015 in order to focus on developing the D programming language.
In January 2022, Alexandrescu began working at
Nvidia
Nvidia Corporation ( ) is an American multinational corporation and technology company headquartered in Santa Clara, California, and incorporated in Delaware. Founded in 1993 by Jensen Huang (president and CEO), Chris Malachowsky, and Curti ...
as a Principal Research Scientist.
Contributions
The D Programming Language
Along with Walter Bright, Andrei has been one of the two main designers of the
D Programming Language
D, also known as dlang, is a multi-paradigm system programming language created by Walter Bright at Digital Mars and released in 2001. Andrei Alexandrescu joined the design and development effort in 2007. Though it originated as a re-enginee ...
, and the principal maintainer of the standard library Phobos from 2007 to 2019. He is the founder of the D Language Foundation. His contributions include the ranges module. He is the author of "The D Programmming Language" book.
Expected
Expected is a
template
Template may refer to:
Tools
* Die (manufacturing), used to cut or shape material
* Mold, in a molding process
* Stencil, a pattern or overlay used in graphic arts (drawing, painting, etc.) and sewing to replicate letters, shapes or designs
C ...
class for C++ which is on the C++ Standards track. Alexandrescu proposes Expected as a class for use as a return value which contains either a T or the exception preventing its creation, which is an improvement over use of either return codes or exceptions exclusively. Expected can be thought of as a restriction of sum (union) types or algebraic datatypes in various languages, e.g.,
Hope
Hope is an optimistic state of mind that is based on an expectation of positive outcomes with respect to events and circumstances in one's own life, or the world at large.
As a verb, Merriam-Webster defines ''hope'' as "to expect with confid ...
, or the more recent
Haskell
Haskell () is a general-purpose, statically typed, purely functional programming language with type inference and lazy evaluation. Designed for teaching, research, and industrial applications, Haskell pioneered several programming language ...
and Gallina; or of the error handling mechanism of Google's Go, or th Result type in
Rust
Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (FeO(OH) ...
.
He explains the benefits of Expected as:
* Associates errors with computational goals
* Naturally allows multiple exceptions in flight
* Switch between "error handling" and "exception throwing" styles
* Teleportation possible across thread boundaries, across nothrow subsystem boundaries and across time (save now, throw later)
* Collect, group, combine exceptions
Example
For example, instead of any of the following common function prototypes:
int parseInt(const string&); // Returns 0 on error and sets errno.
or
int parseInt(const string&); // Throws invalid_input or overflow
he proposes the following:
Expected parseInt(const string&); // Returns an expected int: either an int or an exception
Scope guard
From 2000 onwards, Alexandrescu has advocated and popularized the scope guard idiom. He has introduced it as a language construct in D. It has been implemented by others in many other languages.
compiler
In computing, a compiler is a computer program that Translator (computing), translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primaril ...