adventofcode
/
2019
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Added comments for IntCode interpreter, esp. the code to do with states.

This commit is contained in:
Jonathan Chan 2019-12-09 13:17:33 -08:00
parent 53da35fdac
commit 11b5812975
1 changed files with 12 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
src/IntCode.rkt
View File

@ -15,21 +15,31 @@
(define (program? p) (define (program? p)
(vectorof number?)) (vectorof number?))
;; state =
;; | out number (() -> state)
;; | in (number -> state)
;; | halt program
(define-type state (define-type state
(out [value number?] [resume procedure?]) (out [value number?] [resume procedure?])
(in [resume procedure?]) (in [resume procedure?])
(halt [program program?])) (halt [program program?]))
;; resume-with-output : state -> (values number state)
;; Extract the output, then resume the program.
(define (resume-with-output st) (define (resume-with-output st)
(type-case state st (type-case state st
[out (value resume) (values value (resume))] [out (value resume) (values value (resume))]
[else (error "resume-with-output: Unexpected program state.")])) [else (error "resume-with-output: Unexpected program state.")]))
;; resume-with-input : state -> number -> state
;; Resume the program with given input.
(define (resume-with-input st input) (define (resume-with-input st input)
(type-case state st (type-case state st
[in (resume) (resume input)] [in (resume) (resume input)]
[else (error "resume-with-input: Unexpected program state.")])) [else (error "resume-with-input: Unexpected program state.")]))
;; resume-with-io : state -> (listof number) -> (listof number)
;; Run the program, providing input as needed, and collecting output.
(define (resume-with-io st inputs) (define (resume-with-io st inputs)
(type-case state st (type-case state st
[in (resume) [in (resume)
@ -38,6 +48,8 @@
(cons value (resume-with-io (resume) inputs))] (cons value (resume-with-io (resume) inputs))]
[halt (program) '()])) [halt (program) '()]))
;; halt-with-program : state -> program
;; Return program state of halted execution.
(define (halt-with-program st) (define (halt-with-program st)
(type-case state st (type-case state st
[halt (program) program] [halt (program) program]