Kielan

Implementing Algebraic Effects in C “Monads for Free in C”

Microsoft Research Technical Report MSR-TR-2017-23 Daan Leijen Microsoft Research Updated by Kielan Lemons [email protected]

Abstract. We describe a full implementation of algebraic effects and handlers as a library in standard and portable C99, where effect operations can be used just like regular C functions. We use formal operational semantics to guide the C implementation at every step where an evaluation context corresponds directly to a particular C execution context. Finally we show a novel extension to the formal semantics to describe optimized tail resumptions and prove that the extension is sound. This gives two orders of magnitude improvement to the performance of tail resumptive operations (up to about 150 million operations per second on a Core [email protected])

Aerijo

A guide to writing a language grammar (TextMate) in Atom

Tree sitter

• Atom is transitioning to an entirely new way of defining grammars using tree-sitter. This will be enabled by default quite soon now. It is theoretically faster and more powerful than regex based grammars (the one described in this guide), but requires a steeper learning curve. My understanding is that regex based grammars will still be supported however (at least until version 2), so this guide can still be useful. To enable it yourself, go to Settings -> Core and check Use Tree Sitter Parsers

Links for tree-sitter help:

• tree-sitter: the main repo
• tree-sitter-cli: converts a JavaScript grammar to the required C/C++ files
• node-tree-sitter: module to use Tree-sitter parsers in NodeJS
• [My guide on starting a Tree-sitter grammar

MightyPork

#include <stdint.h>

/**
 * Encode a code point using UTF-8
 * 
 * @author Ondřej Hruška <[email protected]>
 * @license MIT
 * 
 * @param out - output buffer (min 5 characters), will be 0-terminated
 * @param utf - code point 0-0x10FFFF

tel

Indentation sensitive parser combinators

An indentation sensitive parser combinator language is one that helps you express ideas like "this parse only succeeds if it's within the current indentation block". The concept is somewhat small and elegant and is implemented in a few libraries. In this writeup, I will use examples from indents.

Background and goal

The direct goal will be to write the sameOrIndented parser combinator with a type

danidiaz

A series of reading lists mostly related to functional programming.