====== Week 11 ======

~~NOTOC~~

===== Channels, CSP, and Go (cont'd) =====

** One more time: **

  * CSP and Go!
  * Hoare's 1978 CSP paper: https://spinroot.com/courses/summer/Papers/hoare_1978.pdf
    * Go implementation of examples from paper: https://godoc.org/github.com/thomas11/csp
  * Rob Pike's Google I/O 2012 - Go Concurrency Patterns: https://youtu.be/f6kdp27TYZs
  * Peter Welch's slides introducing CSP and occam-pi (but we will use Go this semester!)
    * [[courses:cs377-202001:welch-lectures:top|Occam-pi Lecture Notes]]
    * even though we won't be programming in occam-pi, I want to give you a flavor of it
    * because: 
      * ultimate lightweight processes!
      * composition! 
    * **//Objects Considered Harmful//** (slide 27 of [[https://www.cs.vassar.edu/_media/courses/cs377-202001/welch-lectures/motivation.pdf|motivation.pdf]] slides)
    * **//Legoland://** (slide 83-end of [[https://www.cs.vassar.edu/_media/courses/cs377-202001/welch-lectures/basics.pdf|basics.pdf]]) 
      * picking up where we left off, slide 98
      * Go implementation of Legoland

\\ \\ 
  * Demo and codewalk of [[csp-dining-phils|csp-dining-philosophers.go]]
    * Go language features highlighted:
      * channels
      * select
    * Design basis for solution in Go: go routines (processes)
      * room (communicates with philosophers over channels)
        * for philosophers to enter/leave -- at most 4 at a time to prevent deadlocking, 5th philosopher blocks 
      * forks (communicate with philosophers over channels)
      * philosophers (communicate with forks over channels) \\ \\ 

  * Demo and codewalk: [[courses:cs377-202001:sieve|Sieve of Eratosthenes]] (Prime Number Sieve) 
    * copy the sample code from my directory to yours:
      * cd into the directory where you have your sample Go code
      * ''cp -r /home/mlsmith/cs377-examples/Go/sieve.go ~/''
    * Go language features highlighted:
      * Only one looping construct in Go: for loop 
        * all three parts are optional: init statement, conditional expression, post statement
      * channel declarations in function headers
        * can specify syntactically whether channel is for reading from: <code><-chan</code> or writing to: <code>chan<-</code>// //
  * Assignment 5 posted
    * Sort Pump Gophers {{sort-pump.pdf|PDF}}
    * Due: Friday, Nov 13th