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1 files changed, 17 insertions, 0 deletions

diff --git a/js/games/nluqo.github.io/~bh/61a-pages/Lectures/2.1/cons.scm b/js/games/nluqo.github.io/~bh/61a-pages/Lectures/2.1/cons.scm
new file mode 100644
index 0000000..300027e
--- /dev/null
+++ b/js/games/nluqo.github.io/~bh/61a-pages/Lectures/2.1/cons.scm
@@ -0,0 +1,17 @@
+; implementation of pairs as functions
+
+(define (cons x y)
+  (lambda (which)
+    (cond ((equal? which 'car) x)
+	  ((equal? which 'cdr) y)
+	  (else (error "Bad message to CONS" which)) )))
+
+
+(define (car pair)
+  (pair 'car))
+
+(define (cdr pair)
+  (pair 'cdr))
+
+
+