There's nothing wrong with writing in Bash instead of Bourne as long as your shebang line points to
shebang shebang shebang !
shebooms shebooms shebooms !
-Ricky Martin's "Shebang Line" (Columbia Records 2000)
Anyone who marked more than 50 feet, I question your honest or ability to estimate linear feet. If you think you have more than 50 linear feet of filled bookshelving, get out a tape measure and prove it to yourself.
50 feet is a LOT of shelf space.
A $2 2x4 ripped down the center and cut into 4' lengths makes great supports for 1' wide 4' long shelves that won't sag.
a 5 shelf bookcase = 20' of linear shelving
with two of these you're already at 40' and can easily make up the difference to get to 50'.
I bet most little kids have 3 x 3' shelves for their books.