apg

Techniques for Ensuring Software Correctness: What Worked in Past and Present (Quick revision of 2016 comment on Lobste.rs)

I find it helps to look to prior successes and tradeoffs to try to understand how to best do engineering. People and teams I've identified as independent inventors of software engineering were Bob Barton of Burroughs B5000, Dijkstra w/ THE OS, and Margaret Hamilton in Apollo & 001 Tool Suite. Each had pieces of the problem with some culminating with later work into the TCSEC and Orange Book’s B3/A1 classes of high-assurance security. At IBM, Fagan invented formal, software inspections for lower defects. Harlan Mills invented a method, Cleanroom Software Engineering, that consistently resulted in low defects even on first use. Became my baseline.

In parallel, the safety-critical embedded community continued using all kinds of their own methods or variations on common ones. They often published "lessons learned" reports with useful information. CompSci researchers continued working on

Ircama

Configuring the Digispark ATTINY85 board for Arduino IDE and upgrading the bootloader

Warning: this document has to be updated by pointing to https://github.com/SpenceKonde/ATTinyCore

This note describes the configuration of an ATtiny85 based microcontroller development board named Digispark and similar to the Arduino line. It is available in many online marketplaces for roughly 1 dollar (e.g., Ebay, Amazon, AliExpress) and is shipped fully assembled, including a V-USB interface (a software-only implementation of a low-speed USB device for Atmel's AVR microcontrollers). Coding is similar to Arduino: it uses the familiar Arduino IDE and is already provided with a ready-to-use bootloader (

pathikrit

Libraries

• Web Server: Play (framework) or http4s (library)
• Actors: akka
• Asynchronous Programming: monix (for tasks, reactors, observables, scheduler etc)
• Authentication: Silhouette
• Authorization: Deadbolt
• Command-line option parsing: case-app
• CSV Parsing: kantan.csv
• DB: doobie (for PostgreSQL)

vmarquez

  object Test {   
    import scalaz.{Lens,State}   
    case class BlahConfig(server: Int, l: List[Int]) 
     
    def doStuff(i: Int) = State[BlahConfig,Int]( c => (c.copy(l = i :: c.l), c.server) ) 
   
    case class FooConfig(val password: String) 
   
    def doSomeStuff(i: Int) = State[FooConfig, String](c =>(c, c.password)) 
    

merijn

data MyState s a = MyState (s -> (a, s))

get :: MyState s s
get = undefined

put :: s -> MyState s ()
put = undefined

modify :: (s -> s) -> MyState s ()
modify = undefined