String and list of strings concatenation

From: Roger J. Meier (r_at_tac.ch)
Date: 10/31/03 

Date: Fri, 31 Oct 2003 16:34:01 +0100

A procedure with the following signature

   proc setMessage {msg args}

should consider "msg" as a string and "args" as a list of
strings with arbitrary content, including curly braces ({,
}), newline sequences (\r, \n) and double quotes (").

The goal is to return a string consisting of lines of text
which are separated by newline.

e. g.

setMessage a b c

gives

a
b
c

setMessage a\nb b c

gives

a
b
b
c

setMessage a\nb

gives

a
b

I came up with the following solution:

proc setMessage {msg args} {
    if {[llength $args]} {
       set all [join [eval list [list $msg] $args] "\n"]
    } else {
       set all $msg
    }
    return $all
}

It works with arbitrary and complex strings, even containing
braces and such. But... just to know: Is there a simple or
more elegant way to join "all"? It's not really important,
but I'm just wondering if I hit a good solution...

-- Roger