Finder open using syntax

Question

How do a use a variable for the application to use in the finder open file-name using the-application-path? I am trying to avoid having to code the disk name.
This script fails on open ... using ...
Background:
I am trying to open a script in the applescript script editor without having an associated blank document also be openned.
set appName to "Script Editor"
-- Name of our process
set processName to "Script Editor"
--set fileToPrint to "Macintosh-HD:Applications:Applescript files:clipboard to file name.app"
--set fileToPrintAlias to fileToPrint as alias
set fileToPrint to choose file with prompt "Select an applescript source file."
set theHD to path to startup disk
set theHD to (theHD as text)
log "theHD = " & theHD
set appPath to theHD & "Applications:AppleScript:Script Editor.app"
log "appPath = " & appPath
tell application "Finder"
   --open fileToPrint using "Macintosh-HD:Applications:AppleScript:Script Editor.app"
   open fileToPrint using my appPath
end tell
tell application appName
   activate
end tell
Robert

Answer 1

Hello
Try something like the following code.
set a to choose file with prompt "Select an applescript source file."
set app_ to "/Applications/AppleScript/Script Editor.app" as POSIX file as string
tell application "Finder"
open a using application file app_
end tell
It seems to work as expected under OSX10.2.8 at hand.
Not sure for 10.4, though.
H