Yan Cui
I help clients go faster for less using serverless technologies.
Bit Syntax in Erlang
One of the often under-appreciated features of Erlang is its Bit Syntax for parsing and pattern matching binary data at a bit level. For instance, to pare TCP segments you can write something along the line of:
The same capability can be applied to anything binary protocols, such as video encoding, imaging, or UDP.
Imitating with F# Computation Expressions
Whilst this capability is not built into F#, or any other language that I know of for that matter, we do have a very powerful, and robust feature in F# in Computation Expressions.
With computation expressions, I was able to create a small library that allows you to write and read data to and from a stream at a bit level. With the bitWriter and bitReader workflows you will be able to write and parse TCP headers with code like the following:
The library is available via Nuget:
please give it a try, and let me know if you find any bugs here.
p.s. there is still much work to be done on the library. For instance, it’s allocating a new buffer array for each workflow rather than using a buffer pool. If you find this library useful and in need for greater performance, please feel free to contribute and help improve the performance of this library.
Whenever you’re ready, here are 3 ways I can help you:
- Production-Ready Serverless: Join 20+ AWS Heroes & Community Builders and 1000+ other students in levelling up your serverless game. This is your one-stop shop to level up your serverless skills quickly.
- Do you want to know how to test serverless architectures with a fast dev & test loop? Check out my latest course, Testing Serverless Architectures and learn the smart way to test serverless.
- I help clients launch product ideas, improve their development processes and upskill their teams. If you’d like to work together, then let’s get in touch.
Pingback: F# Weekly #39-41, 2014 | Sergey Tihon's Blog
Interesting library, I was wondering if you have thought about using the type system to check if the two workflows (write/read) match. I wrote a snippet some time ago (http://fssnip.net/jL) but it would be interesting to see if there is any practical application to this.
That’s a great idea, I hadn’t thought of that. I imagine it’ll be useful in any .Net-to-.Net client server scenarios, the type safety it provides will be pretty awesome :-)
My original motivation for this library was to make it easier for us to integrate our .Net code with our Erlang code which takes advantage of its bit syntax to make more socket protocols more compact (e.g. using 3 bits to represent a number instead of 8 for instance).
Pingback: Year in Review, 2014 | theburningmonk.com