As one comp.lang.tcl poster summarized,
  source YOUR_FILE
in tclsh/wish/whatever.

There are a lot of other possibilities, in fact.  CL
argues that Tcl isn't so much a language as a collection
of tools, and different craftsmen favor almost disjoint
bundles of implements for their specialties.

Here's a bit more detail about the possibilities:  those
sitting at a MacOS or Win* desktop will first launch an interpreter
by double-clicking on the appropriate installed icon.  They'll see
then (perhaps along with other elements) a text area with a %
prompt.  The correct action in this case is to type
  source YOUR_FILE
at the %.

Win* users might eventually have occasion to command something
like
  "\Program Files\tcl\bin\tclsh83" YOUR_FILE
at a DOS-box command line.

There are also several ways to make YOUR_FILE itself "clickable".
If its name is of the form
  NAME.tcl
it should be, already.  Even once its launched, there might still
be issues about this mode; a conventional installation "hides the
console" when used this way.  As with most things Tcl, though,
it's possible to adjust this behavior.

''KBK'' (9 January 2001) - Specifically, if you always want the
console to show when you launch the program, put
    catch { console show }
somewhere in the script.  Popping up a console when you have another
GUI is a little annoying, though.  If your app has a menu bar, putting
a console control in the system [menu] is a better approach.

----

LV: On Unix, several options are available.  One can start up a tclsh
or wish and then source in the file, as mentioned above.  In addition,
one can start wish or tclsh up with the name of the text file - the
file immediately executes.  Also, one can add, as the first line of the
text file, something similar to:

#! /path/to/tcl/or/wish

and then save the file, and from the command line invoke the chmod 
unix command with an initial argument of 755 or rwxr-xr-x or u+rwx,g+rx,o+rw and then the file can be directly invoked.

WARNING!  In this last case, the pathname in the #! is likely to need to be short - while the length varies from implementation to implementation, most unix-like systems implement some sort of maximum value (sometimes as short as 30 characters) for the line.

RS: See [exec magic] for the coolest way, where you don't have to know where ''tclsh'' or ''wish'' sit...


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LV: On the Mac, there is a mechanism for setting the owner of a text file in such a way that the application is directly invokable.  In fact, the Mac Tcl/Tk comes I believe with an app/icon onto which you can drop your tcl text files and their owners will be set appropriately.
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