HOPL IV Trip Report

Conor Hoekstra · September 6, 2021

This trip report is a bit delayed, but better late than never. HOPL stands for History of Programming Languages and is a conference that happens roughly once every 14 years. The past HOPL conferences happened in the following years:

HOPL IV took place from June 20 to 22. HOPL IV was originally supposed to take place in 2020, but due to COVID it was postponed to 2021 and happened virtually.


Here is a list of all the talks given and hyperlinks if you would like to watch them.

Language Talk Authors/Speaker
APL APL Since 1978 Roger Hui, Morten Kromberg
C++ Thriving in a crowded and changing world: C++ 2006-2020 Bjarne Stroustrup
Clojure A History of Clojure Rich Hickey
Fortran History of Coarrays and SPMD Parallelism in Fortran John Reid et al.
D Origins of the D Programming Language Walter Bright et al.
Emacs Lisp Evolution of Emacs Lisp Stefan Monnier, Michael Sperber
F# The Early History of F# Don Syme
Groovy A history of the Groovy programming language Paul King
JavaScript JavaScript: The First 20 Years Allen Wirfs-Brock, Brendan Eich
LabVIEW LabVIEW Jeff Kodosky
Logo History of Logo Cynthia Solomon et al.
MATLAB A History of MATLAB Jack Little, Cleve Moler
Objective-C The Origins of Objective-C at PPI/Stepstone and its Evolution at NeXT Brad Cox et al.
Oz A history of the Oz multiparadigm language Peter Van Roy et al.
S/R S, R and Data Science John Chambers
Smalltalk The Evolution of Smalltalk from Smalltalk-72 through Squeak Daniel Ingalls
SML The History of Standard ML David MacQueen et al.
Verilog Verilog HDL and its ancestors and descendants Peter Flake et al.
  Hygienic Macro Technology William D. Clinger, Mitchell Wand


My top two favorite talks were the histories of APL and Clojure. They were both great talks but I am also a bit biased because APL is my #1 favorite language and Clojure is my #3 favorite language. The other highlight of the conference were the conversations that took place in between the talks. I spent a lot of time talking with Aaron Hsu, author of Co-dfns, a GPU-accelerated APL compiler. At one point, we had a great group conversation with the following folks:

Several folks asked if the discussion was recorded but sadly it was not. However, there is potential to reconvene the panel at some point or have them on ArrayCast, a podcast on array languages that I host.

Thank You

Thanks to the volunteers and organizers of the conference. It was great to meet and chat with programming language folks online.

Feel free to leave a comment on the reddit thread.

Hope to see you in person at a conference 2022!

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