====== Week 10 ======

~~NOTOC~~

===== Channels, CSP, and Go =====


  * Peter Welch's [[courses:cs377-202201:welch-lectures:top|Occam-pi Lecture Notes]]

  * Go demo and starter code
    * copy from Marc's directory into your ''cs377'' course directory: <code>
$ cd ~/cs377
$ cp -r /home/mlsmith/cs377-examples/Go ./
</code>
    * you should see the following files in your local ''Go'' directory: <code>
$ ls
csp-dining-phils.go phils-out.txt sieve.go sort-pump.go
$
</code>

  * Demo and codewalk of ''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)
    * To run this program: <code>
$ go run csp-dining-philosophers.go
</code>

  * Demo and codewalk: Sieve of Eratosthenes (Prime Number Sieve) ''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>
    * To run this program: <code>
$ go run sieve.go
</code> // // 

  * Assignment 5 posted
    * Sort Pump Gophers {{sort-pump.pdf|PDF}}
    * see a similar example in occam on slides 13--31 of PHW's [[https://www.cs.vassar.edu/_media/courses/cs377-202201/welch-lectures/replicators.pdf|replicators]] lecture notes
    * Due: Friday, Nov 18th