λ CS 251 : Principles of Programming Languages .

Staff / Hours

Instructor: Lyn Turbak, SCI E126
Drop-in hours TBA (in Lyn's office = SCI E126): (see the drop-ins calendar for the most up-to-date info):

Tutors:: Hope Anderson, Ngina Kariuki, Sherry Xu, Yige Zhu

Tutor Drop-ins (start the week of Feb 04)
(see the drop-ins calendar for the most up-to-date info)

• Tuesdays 7-9pm: Ngina Kariuki in SCI 270
• Wednesdays 7-9pm: Sherry Xu in E101
• Thursdays 6-8pm: Hope Anderson in E111
• Friday 6-8pm: Yige Zhu in E111

Schedule (jump to now)

• Class meetings:
  • Morning section (01): SCI E111 Monday, Wednesday, Thursday 8:30am - 9:45am
  • Afternoon section (02): SCI 268 Monday/Thursday 2:55-4:10pm, Wednesday 3:50-5:05pm

Here is a tentative calendar for the semester. The future and recent past, as recorded here, are subject to revision at any time. See the long-term schedule on the syllabus for the big picture. Future slide links may be to slides from Fall 2018; in many cases these will be unchanged or edited lightly for this semester.

Mon	Wed	Thu
28 January 251 class starts today start big ideas; what is this course about?; PL paradigms and dimensions; why you want to take this course [slides 1-14, solns] quick administrivia (see syllabus); more on Wed. quick interactive session with Racket PL parts overview; syntax, start dynamic semantics; first dynamic semantics exercise ([slides 15-19]) PS0 out; get to know you, study administrivia, install Racket PS1 out; syntax, comparing languages, Racket, big-step vs. small-step semantics. Assign: PS0 Introductions Assign: PS1 Evaluating Languages	30 January more PL parts; remaining dynamic semantics exercises [slides 20-21, solns] course administrivia (see syllabus) discussion of investigating a section afternoon CS251 section PS0 due	31 January static semantics exercises, pragmatics (App Inventor raffle); [slides 22-27, solns]
04 February metaprogramming overview [slides 28-32] start Racket expressions and declarations; big-step semantics [slides 1-21, solns]	06 February continue Racket expressions and declarations; big-step semantics exercise; definitions, small--step semantics [slides 21-44, solns]	07 February start functions and substitution model [slides 1-15, solns] PS1 dueish (on Fri) PS2 out (Sat); semantics, Racket recursion, Racket lambda semantics and stack depth Assign: PS2 Antics with Semantics
11 February wrap up functions; recursion; order of growth in time and space [slides 16-26, solns] PS1 hardcopy solutions distributed	13 February cons cells, pairs, lists [slides 1-25, solns]	14 February cons vs. list vs. append [slides 26-30, solns] Start divide-conquer-glue list recursion in Racket [slides 1-13, solns] PS2 dueish (on Friday) PS3 out (Sat); Racket lists and list recursion Assign: PS3 Racket List Recursion
18 February Presidents Day (Monday schedule for Tue. Feb 19) Finish divide/conquer/glue list recursion in Racket [slides 14-23, solns] PS2 hardcopy solutions distributed	20 February Start local binding with let [slides 1-17 , solns]	21 February Finish local binding (scope, contours, let*, letrec)[slides 18-32, solns]
25 February first-class functions, nameable, passable, returnable, storable, creatable in any context [slides, solns] PS3 dueish	27 February higher-order list functions, map , filter [slides 1-15, solns] PS4 out; first-class functions and higher-order list operations Assign: PS4 First-Class Fun	28 February more higher-order list functions, foldr, foldr-ternop [slides 15-23, solns] PS3 hardcopy solutions distributed
04 March iteration and tail recursion, foldl [slides 1-30ish (4up pdf, 1up pdf), pptx), solns] PS4 dueish (Tue)	06 March tail recursion review; iterate and iterate-apply; [slides 30ish-41 (4up pdf, 1up pdf, pptx), solns] PS4 hardcopy solutions distributed PS5 out; iteration and tail recursion Assign: PS5 Iterate Until Done	07 March finish tail recursion; genlist and genlist-apply [slides 30ish-51 (4up pdf, 1up pdf, pptx), solns] symbols and quoted lists; s-expression trees [slides 1-10, solns]
11 March metaprogramming appetizer 1 processing s-expression trees; first metalanguage examples = processing Racket-expressions-as-s-expressions [slides 11-16, solns]	13 March metaprogramming appetizer 2 an introduction to Postfix [specification and examples of PostFix language from Design Concepts in Programming Languages.] Postfix interpretation in Racket [slides 1-6] PS5 (Wed) dueish	14 March metaprogramming appetizer 3 Postfix interpretation in Racket [slides 4-20] Flesh out configuration-based PostFix interpreter in postfix-config-tail-starter.rkt (solutions are in postfix-config-tail-simple.rkt) Bells and whistles in postfix-config-tail-fancy.rkt; error handling, printing of intermediate configurations, more modular handling of arithops and relops Add `avg` command to PostFix. BEFORE LECTURE NEXT TIME; install Virtual Box VM and run SML installer on it Assign: PS6 Practicing PostFix
18 March BEFORE LECTURE TODAY; install Virtual Box VM and run SML installer on it Wrap-up of Postfix-in-Racket interpreter [slides 21-23] Using iterate-apply to iterate through Postfix commands/stack configurations [postfix-config-iterate-simple.rkt, postfix-config-iterate-fancy.rkt Implementation of PostFix interpreter via `foldl` to combine commands-as-stack-transformers [postfix-transform-simple.rkt, postfix-transform-fancy.rkt] Begin introduction to SML, including booleans, conditionals, recursion, [slides (w/blanks) 1-14, solns] PS5 hardcopy solutions available	20 March Practical SML programming in SML in csenv and Emacs using `.sml` and `*sml*` buffers (rather than terminal) and `use` [slides 15-22, solns] GNU Emacs Reference Card handed out More introduction to SML, including `fib` exercise, strings, characters, tuples, and pattern matching on tuples. [slides 23-28, solns]	21 March Spring Break No class today
25 March Spring Break No class today	27 March Spring Break No class today	28 March Spring Break No class today
01 April Review introduction to SML slides covered before break; new material includes tupled vs. curried arguments, higher-order functions, `sumUpTo/makeLinear' exercise [slides (w/blanks) 29-31, solns]	03 April Finish introduction to SML; function composition, tail recursion, scoping gotchas, `fun` vs. `and` (mutually recursive functions), `fib_iter` exercise, `let`, and more tuple pattern matching [slides (w/blanks) 32-40, solns] Start list processing in SML; lists, list operations [slides (w/blanks) 1-6, solns] PS6 dueish PS7 out; PostLoop, Backus paper, introductory SML programming Assign: PS7 Resistance is Futile. You Will Be SMLated.	04 April More list processing in SML; pattern matching on lists; list accumulation, `map`/`filter`/`foldr` and friends in SML [slides (w/blanks) 7-16, solns]
08 April Finish list processing in SML; SML list function exercises [slides (w/blanks) 17-18, solns] Start SML sum-of-product datatypes; figures, options, lists [slides 1-9 w/blanks, solns]	10 April Finish SML sum-of-product datatypes; binary trees, binary search trees [slides 10-23 w/blanks, solns] Discuss upcoming PS8 Problem 2 on 2-3 trees PS6 hardcopy solutions distributed PS7 dueish	11 April Start SML modules and abstract datatypes; mathlib, rational numbers, signature matching [slides 1-22] PS8 out; 2-3 trees, sets Assign: PS8 Set Yourself Free
15 April Patriots Day No class today	17 April Finish SML modules and abstract datatypes; sets [slides 23-31] Discuss PS8 Problems 3 (FunSet) and 4 (Operation Tree Set) PS7 hardcopy solutions distributed	18 April Metaprogramming; interpreters, compilers, and language derivations; language derivations exercise [slides 1-19]
22 April Metaprogramming; bootstrapping [slides 20-30] Start PostFix in SML; sum-of-product abstract syntax slides 1-3 PS8 dueish PS9 out; metaprogramming, PostFix-in-SML, Intex Assign: PS9 I Never Metalanguage I Didn't Like	24 April More PostFix in SML; PostFix interpreter in SML leveraging pattern matching; error handling in interpreter [slides 4-13 (which already include interpreter solns on slide 8) PS8 hardcopy solutions distributed	25 April Finish PostFix in SML; s-expressions in SML [slides 14-24 Introduction to Intex; sum-of-product abstract syntax; intex interpreter; static arg checking [slides 1-16 w/blanks]
29 April Finish Intex; compiling Intex to Postfix [slides 17-20, solns]	01 May Ruhlman Conference No class today	02 May Introduction to Bindex; Bindex naming features; sum-of-product ASTs; free variable rules and calculation[slides 1-12 w/blanks, solns] PS9 dueish PS10 out; mini-FP interpreter (solo), Bindex, Valex Assign: PS10 Open to Interpretation
06 May Bindex wrap-up; environments; Bindex interpreter; Sigmex = Bindex + sigma [slides 12-26 w/blanks, solns]	08 May Valex; multiple types of values, conditionals, dynamic typing, desugaring [slides w/blanks, solns]	09 May HOFL = Valex + first-class functions; static vs. dynamic scope; environment model of evaluation; closures [handout] PS9 hardcopy solutions available PS10 dueish (Fri)
13 May Reading Period PS10 hardcopy solutions available	15 May Final Exams	16 May Final Exams PS11 out. Compex solo problem, Valex desugaring, HOFL. On PS11, all problems (including the solo problem) are optional extra credit problems. Assign: PS11 A Hofl Lot (all problems are *optional* extra credit problems, including solo problem)
20 May Final Exams All leftover CS251 work due by end of day on Tue. May 21	22 May	23 May