Using Quicksilver and Applescript to Keep a Stack of Safari URLs

My friend posted this question on Hacker News. I answered:

If you’re on a Mac and you’re using Safari you might like Urly (http://www.zenonez.com/urly/news.html). It lets you make a pretty basic stack of browser links. If you don’t like that (and you’re a Quicksilver user), it might be worth writing some Quicksilver triggers to push and pop urls using a text file as a stack.

I decided I might as well code my solution. I’d never written any Applescript before, so what have is cobbled together from various examples I found online and very likely not the best way to do it.  I made two scripts.
 
bpush.scpt:
tell application "Safari"
 
set theurl to URL of front document
end tell
 
set clipFil to (path to documents folder as text) & "tobrowse.txt"
try
close access file clipFil
end try
set filRef to open for access file clipFil with write permission
write (return & (theurl)) to filRef starting at eof
close access filRef
tell application "Safari" to activate
bpop:scpt:
set clipFil to (path to documents folder as text) & "tobrowse.txt"
 
try
close access file clipFil
end try
 
set filRef to open for access file clipFil with write permission
set filetext to (read filRef)
set thelist to every paragraph of filetext
set theurl to item (length of thelist) of thelist
set item (length of thelist) of thelist to ""
set newtext to (thelist) as text
set eof of filRef to 0
write newtext to filRef
close access filRef
 
tell application "Safari"
activate
set URL of document 1 to theurl
end tell
I can activate these by just typing bpush and bpop into Quicksilver. I’ve tried using this while browsing for the past hour or so and it’s definitely too soon to say for sure, but I think I might actually use these.