added code snippets

Author: lorossi

snippets/racket/2022-01-21.rkt

@@ -0,0 +1,18 @@
+#lang racket
+
+(define-syntax block
+ (syntax-rules (then where <-)
+  ((_ (case1 ...)
+  then (case2 ...)
+  where (v <- a b) ...)
+    (begin
+      ((let ((v a) ...) case1 ...)
+      (let ((v b) ...) case2 ...))))))
+
+(block
+  ((displayln (* x y)))
+  then
+  ((displayln (+ x y)))
+  where
+  (x <- 2 0)
+  (y <- 3 2))

snippets/racket/2022-06-16.rkt

@@ -0,0 +1,5 @@
+#lang racket
+
+(define list-to-compose (lst)
+    (foldr (lambda (x y) (list x y)) '() lst))
+