proc a> {a args} {eval [list interp alias {} $a {}] $args}
  a> p puts ; a> s set
  a> sr list ::S ; a> ss s [sr] ; ss {1 2 3}
  a> . eval {lindex [ss] 0}
  a> drop eval {ss [lreplace [ss] 0 0]}
  a> ex eval {eval [.] ; drop}

  a> ? s errorInfo

  % proc a> {a args} {eval [list interp alias {} $a {}] $args}
  % proc |ex {s x} {foreach a [split $x |] {eval $s $a}}
  % set n 0
  0
  % |ex {a> c[incr ::n] puts} {a|b|c}
  % c1
  a
  % c2
  b
  % c3
  c

  % proc a> {a args} {eval [list interp alias {} $a {}] $args}
  % a> a< interp alias {}
  a<
  % a> g uplevel #0
  g
  % a< g
  uplevel #0

  % |ex a> {pk proc | g uplevel #0 | r puts "in the end, nothing"}