I propose changing /<n> to /<id>.

There is no one-to-one correspondence between n-th snippet and snippet id because we have the name space for main, startup and error.
(Note: When the re-run command was implemented, we had just only one name space for any snippet)

It makes re-run difficult.
When we re-run main snippet, we have to add the number of startup snippets and the number of erroneous snippets which appear prior to the snippet what we want to re-run.
It is very confusing for users.

-> int n = 10
| Added variable n of type int with initial value 10

-> Math.sqrt(n)
| Expression value is: 3.1622776601683795
| assigned to temporary variable $2 of type double

-> n = 30
| Variable n has been assigned the value 30

-> /list

   1 : int n = 10;
   2 : Math.sqrt(n)
   3 : n = 30

-> /2
import java.io.*;

-> /list all

  s1 : import java.util.*;
  s2 : import java.io.*;
  s3 : import java.math.*;
  s4 : import java.net.*;
  s5 : import java.util.concurrent.*;
  s6 : import java.util.prefs.*;
  s7 : import java.util.regex.*;
  s8 : void printf(String format, Object... args) { System.out.printf(format, args); }
   1 : int n = 10;
   2 : Math.sqrt(n)
   3 : n = 30

-> /10
Math.sqrt(n)
| Expression value is: 5.477225575051661
| assigned to temporary variable $4 of type double