Just another update

Task/Generic-swap/Aime/generic-swap.aime

@@ -0,0 +1,12 @@
+void
+__swap(&, &,,)
+{
+    set(0, $3);
+    set(1, $2);
+}
+
+void
+swap(&, &)
+{
+    xcall(xcall, __swap);
+}

Task/Generic-swap/Emacs-Lisp/generic-swap-1.l

@@ -0,0 +1,6 @@
+(defun swap (a-sym b-sym)
+  "Swap values of the variables given by A-SYM and B-SYM."
+  (let ((a-val (symbol-value a-sym)))
+    (set a-sym (symbol-value b-sym))
+    (set b-sym a-val)))
+(swap 'a 'b)

Task/Generic-swap/Emacs-Lisp/generic-swap-2.l

@@ -0,0 +1,2 @@
+(defmacro swap (a b)
+  `(setq ,b (prog1 ,a (setq ,a ,b))))

Task/Generic-swap/Emacs-Lisp/generic-swap-3.l

@@ -0,0 +1,8 @@
+(require 'cl)
+(defmacro swap (a b)
+  `(psetf ,a ,b
+          ,b ,a))
+
+(setq lst (list 123 456))
+(swap (car lst) (cadr lst))
+;; now lst is '(456 123)

Task/Generic-swap/NewLISP/generic-swap.newlisp

@@ -0,0 +1 @@
+(swap a b)

Task/Generic-swap/UNIX-Shell/generic-swap-1.sh

@@ -0,0 +1,10 @@
+$ swap() { typeset -n var1=$1 var2=$2; set -- "$var1" "$var2"; var1=$2; var2=$1; }
+$ a=1 b=2
+$ echo $a $b
+1 2
+$ swap a b
+$ echo $a $b
+2 1
+$ swap a b
+$ echo $a $b
+1 2

Task/Generic-swap/UNIX-Shell/generic-swap-2.sh

@@ -0,0 +1,10 @@
+$ swap() { local var1=$1 var2=$2; set -- "${!var1}" "${!var2}"; declare -g "$var1"="$2" "$var2"="$1"; }
+$ a=1 b=2
+$ echo $a $b
+1 2
+$ swap a b
+$ echo $a $b
+2 1
+$ swap a b
+$ echo $a $b
+1 2