kmicinski

#lang racket

;; 0 argument function which calls itself
;; (with zero arguments...)
(define (loop) (loop))


(if #t 42 (loop))

;; if cannot be a function, because if it were,

kmicinski

use std::collections::{HashMap, HashSet};

type Clause = Vec<i32>;
type Clauses = HashSet<Clause>;
type Trail = Vec<TrailEntry>;
type Assignment = HashMap<i32, bool>;

#[derive(Debug, Clone)]
enum TrailEntry {
    Decision(i32),

kmicinski

fn run(clauses: &Clauses) {

let mut state = DpllState::Running(Vec::new(), Assignment::new(), clauses.clone()); loop {

match &state {

DpllState::Unsat => {

println!("UNSAT"); break;

} DpllState::Sat(trail) => {

println!("SAT {:?}", trail);

kmicinski

;; Traditional Abstract DPLL (no clause learning)
;; See this paper: https://homepage.cs.uiowa.edu/~tinelli/papers/NieOT-JACM-06.pdf
#lang racket

(define (clause? cl)
  (match cl
    [`(,(? integer? x) ...) #t]
    [_ #f]))

kmicinski

#lang racket

;; Direct style
(define (filter f l)
  (match l
    ['() '()]
    [`(,hd . ,tl) (if (f hd) (cons hd (filter f tl)) (filter f tl))]))

;; Tail recursive version
(define (filter-tl f l)

kmicinski

#lang racket
(provide (all-defined-out))
;;
;; CIS352 (Fall '24) Racket Warmup
;;

(define (square x) (* x x))

;; return the Euclidian distance between x0,y0 and x1,y1
(define (euclid-distance x0 y0 x1 y1)

kmicinski

;; Relational algebra
#lang racket

(define relation? symbol?)
(define atom? symbol?) ;; atomic lits are symbols

;; variables must be explicitly tagged, not 'x, but '(var x)
(define (var? x) (match x [`(var ,(? symbol? x)) #t] [_ #f]))
(define (var-or-atom? x) (or (atom? x) (var? x)))

kmicinski

;; Challenge: find all the bugs in this small functional compiler
#lang racket

(provide (all-defined-out))

(define verbose-mode (make-parameter #t))
(define i-am-a-mac (make-parameter #f))

;; 
;; Our compiler will have several layers

kmicinski

#lang racket
;; v0.0 April 8, 2024 -- WORKING NOTES (could have bugs!) 

;; Apply/Eval Refactoring -- Semantics Homework
;;
;; Kris Micinski (kkmicins@syr.edu and krismicinski@gmail.com)
;;
;; Warning: may be buggy, please contact kris if you notice
;; obvious bugs.
(provide (all-defined-out))

kmicinski

#lang racket

;; The Church-encoded number N is represented as:
;; - A function (λ (f) ...) which takes a function f
;; - Returns a function which accepts an argument x
;;   and applies f N times to x

;; two, Church-encoded as a *Racket* lambda
(λ (f) (λ (x) (f (f x))))