I just discovered to my chagrin that the Satimage.osax understands and will coerce Tilde-based paths.
It's tremendously faster than talking to System Events.
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# Auth: Christopher Stone
# dCre: 2017/01/24 02:00
# dMod: 2017/01/24 02:23
# Appl: Satimage.osax
# Task: absoluteURL examples.
# Libs: None
# Osax: None
# Tags: @Applescript, @Script, @Satimage.osax, @absoluteURL, @Examples
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set downloadsFolderPath to "~/Downloads/"
set myFURL to absoluteURL downloadsFolderPath as path
--> file "Mercury:Users:myUserName:Downloads"
set myAlias to absoluteURL downloadsFolderPath as alias
--> alias "Mercury:Users:myUserName:Downloads:"
set myHFSPath to (absoluteURL downloadsFolderPath as alias) as text
--> "Mercury:Users:myUserName:Downloads:"
set myPosixPath to absoluteURL downloadsFolderPath as unix path
--> "/Users/myUserName/Downloads/"
set myFileURL to absoluteURL downloadsFolderPath as Unicode text -- default
set {desktopFolder, downloadsFolder} to absoluteURL {"~/Desktop", "~/Downloads"} as alias
--> {alias "Mercury:Users:myUserName:Desktop:", alias "Mercury:Users:myUserName:Downloads:"}
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