ICFP 2021
Sun 22 - Sat 28 August 2021
Mon 23 Aug 2021 00:30 - 01:00 at HOPE - Session 4

I’ll present OmegaC, a probabilistic programming language with counterfactuals originally presented at ICML 2021, from a semanticist’s point of view. Counterfactuals are a new effect that makes it easy to express queries like “how much larger would the output be had the input been 1 larger.” I’ll show that counterfactual execution can actually be viewed as a combination of two features previously thought useless, laziness and dynamic scope, and I’ll present the (surprisingly simple) proof that dynamic scope, and therefore also the counterfactual do operator, is not “syntactic sugar” for other operators (i.e.: not macro-expressible).

Slides (hope.pptx)12.45MiB

Sun 22 Aug

Displayed time zone: Seoul change

23:30 - 01:00
Session 4HOPE at HOPE
23:30
30m
Talk
First-class Names for Effect Handlers
HOPE
Ningning Xie University of Toronto, Youyou Cong Tokyo Institute of Technology, Daan Leijen Microsoft Research
00:00
30m
Talk
Tensor Partial Evaluation
HOPE
Eli Bingham Broad Institute, Fritz Obermeyer Broad Institute of MIT and Harvard, Yerdos Ordabayev Brandeis University, Du Phan UIUC
File Attached
00:30
30m
Talk
Dynamic Scope + Laziness = Counterfactuals
HOPE
James Koppel Massachusetts Institute of Technology, USA, Armando Solar-Lezama Massachusetts Institute of Technology, Zenna Tavares Massachusetts Institute of Technology, Xin Zhang Peking University
File Attached