Bash: manipulating with strings (percent sign)
If you use @fedorqui's resource, you'll see it is going to strip the shortest match of /* from the end of the first positional argument. An example:
example_foo(){ echo ${1%/*}}example_foo path/to/directory/sub_directory# => path/to/directoryIn the example I used the second positional argument since the first is the name of the function.