congame-example-study: use opt-hash-ref to simplify prisoners-dilemma

MarcKaufmann · Nov 12, 2024 · 5ada9ec · 5ada9ec
1 parent 35026d7
commit 5ada9ec
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Showing 3 changed files with 11 additions and 6 deletions.
diff --git a/congame-example-study/info.rkt b/congame-example-study/info.rkt
@@ -10,6 +10,7 @@
     "gregor-lib"
     "forms-lib"
     "koyo-lib"
+    ["monocle-lib" #:version "0.3"]
     "sentry-lib"
     "threading-lib"
     "web-server-lib"))

diff --git a/congame-example-study/prisoners-dilemma.rkt b/congame-example-study/prisoners-dilemma.rkt
@@ -1,6 +1,7 @@
 #lang conscript
 
 (require conscript/survey-tools
+         data/monocle
          racket/match)
 
 (provide
@@ -14,14 +15,15 @@
 (defvar*/instance choices dilemma-choices)
 (defvar choice)
 
+(define (&my-choice)
+  (parameterize ([current-hash-maker hash])
+    (&opt-hash-ref*
+     (get-current-group)
+     (current-participant-id))))
+
 (define (make-choice! choice)
   (with-study-transaction
-    (if (undefined? choices)
-        (set! choices (hash (get-current-group) (hash (current-participant-id) choice)))
-        (set! choices (hash-update
-                       choices (get-current-group)
-                       (λ (ht) (hash-set ht (current-participant-id) choice))
-                       hash)))))
+    (set! choices ((&my-choice) (if-undefined choices (hash)) choice))))
 
 (defstep (intro)
   @md{# Prisoner's Dilemma

diff --git a/conscript/base.rkt b/conscript/base.rkt
@@ -51,6 +51,7 @@
  set!
  values
 
+ parameterize
  with-handlers
 
  ;; Racket Runtime
@@ -132,6 +133,7 @@
       congame-web/components/uploaded-file
       conscript/matchmaking
       conscript/survey-tools
+      data/monocle
       gregor
       koyo/haml
       racket/format