3 HN users recommended this talk3 months2013–2014score 3
Years with an HN recommendation, 2007–2026
Pointed to as the origin story of Hack and a real-world example of OCaml in production.
Julien Verlaguet of Facebook describes applying static analysis and type inference to a very large PHP codebase, using OCaml. The work led to the Hack language.
“Another cool one from CUFP this year is how Facebook is using OCaml to add incremental type inference to their vast PHP code base.” (HN, 2013)
Another cool one from CUFP this year is how Facebook is using OCaml to add incremental type inference to their vast PHP code base. There's (slightly hard to see video) here, but I'm sure Facebook will publicize it more widely when they're ready. [this video]
Facebook using OCaml for incremental type inference on PHP.
Check out Hack for HHVM[0][1][2]. It's a lot saner than PHP, but it's not documented or well known outside Facebook. [0]: Strangle Loop 2013: Keith Adams, Facebook: Taking PHP Seriously [link] [1]: CUFP 2013: Julien Verlaguet, Facebook: Analyzing PHP statically [this video] [2]: HHVM and Hack – Can We Expect Them to Replace PHP? [link]
It's good to hear stories about how FP is being used in industry and I'd like to read more. For those who have an interest in this, I recommend the Commercial Users of Functional Programming workshop ( [link] ). It's where I first heard about Facebook's use of OCaml to create Hack ( [this video] )
I tried looking for something by way of an official announcement or release (preview or otherwise), but as Keith Adams joked, it's impossible it Google it, and the [link] URL he referenced is not correct. Someone in the Q&A pointed that out, so he mentioned that there'd be a post about it on the HHVM blog, but there doesn't seem to be anything about it in the last few months (this talk took place in September). Someone asked Keith Adams on Twitter at the end of October, where Adams said there was nothing to announce yet: [link] The only other thing I could find about it was another talk by Julien Verlaguet (to whom Adams credits the invention of Hack) from October: [this video]
> Last time I checked, the ability to write Javascript using both languages was of experimental and/or novelty use only (hence the "cupholders"). Facebook uses an OCaml js_of_ocaml-based frontend for a large chunk of their production code editing. Not a great video, but here's the CUFP 2013 talk on the topic: [this video]
Facebook's production use of OCaml compiled to JavaScript.
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