A-M baby

Task/Menu/REXX/menu.rexx

@@ -0,0 +1,38 @@
+/*REXX program shows a list, asks user for a selection number (integer).*/
+
+  do forever                           /*keep asking until response OK. */
+  call list_create                     /*create the list from scratch.  */
+  call list_show                       /*display (show) the list to user*/
+  if #==0   then return ''             /*if empty list, then return null*/
+  say right(' choose an item by entering a number from 1 ───►' #, 70, '═')
+  parse pull x                         /*get the user's choice (if any).*/
+
+    select
+    when x=''             then call sayErr "a choice wasn't entered"
+    when words(x)\==1     then call sayErr 'too many choices entered:'
+    when \datatype(x,'N') then call sayErr "the choice isn't numeric:"
+    when \datatype(x,'W') then call sayErr "the choice isn't an integer:"
+    when x<1 | x>#        then call sayErr "the choice isn't within range:"
+    otherwise             leave        /*this leaves the DO FOREVER loop*/
+    end   /*select*/
+  end     /*forever*/
+                                       /*user might've entered 2. or 003*/
+x=x/1                                  /*normalize the number (maybe).  */
+say;  say 'you chose item' x": " #.x
+return #.x                             /*stick a fork in it, we're done.*/
+/*──────────────────────────────────LIST_CREATE─────────────────────────*/
+list_create:   #.1='fee fie'           /*one method for list-building.  */
+               #.2='huff and puff'
+               #.3='mirror mirror'
+               #.4='tick tock'
+#=4                                    /*store number of choices in  #. */
+return                                 /*(above) is just one convention.*/
+/*──────────────────────────────────LIST_SHOW───────────────────────────*/
+list_show: say                         /*display a blank line.          */
+              do j=1  for #            /*display the list of choices.   */
+              say '[item' j"] " #.j    /*display item # with its choice.*/
+              end   /*j*/
+say                                    /*display another blank line.    */
+return
+/*──────────────────────────────────SAYERR──────────────────────────────*/
+sayErr:   say;     say  '***error!***'  arg(1)  x;       say;       return