Added this example of showing a boxed-string

examples/trap.box.in

@@ -0,0 +1,77 @@
+#
+# Prompt for a string and then output it, surrounded by a series of
+# stars!
+#
+#
+#
+ store #1, "Please enter your name:"
+ print_str #1
+
+ # Reads a string from the console - sets the result in register #0
+ int 0x01
+
+ # The following trap removes the newline from the string in #0
+ int 0x02
+
+ call box
+ exit
+
+#
+# This function prints out the string in #0 in a box. For example if the input
+# string in #0 is "Steve" the output will be:
+#
+# *********
+# * Steve *
+# *********
+#
+# Registers ruined:
+# #0
+# #1
+# #10
+#
+:box
+ # string is in #0
+ store #10, #0
+ # find the length
+ int 0x00
+
+ # now we want to print the line of stars to box the string
+ inc #0
+ inc #0
+ inc #0
+ inc #0
+
+:header
+ store #1, "*"
+ print_str #1
+ dec #0
+ jmpnz header
+
+ # print "* $str *"
+ store #1, "\n* "
+ print_str #1
+ store #1, #10
+ print_str #1
+ store #1, " *\n"
+ print_str #1
+
+ # now repeat the process to print stars under the string
+ store #0, #10
+ # find the length
+ int 0x00
+
+ # now we want to print the line of stars to box the string
+ inc #0
+ inc #0
+ inc #0
+ inc #0
+
+:footer
+ store #1, "*"
+ print_str #1
+ dec #0
+ jmpnz footer
+
+ store #1, "\n"
+ print_str #1
+ ret