extract: replace basename&sed w/ zsh variable expansion syntax
extract: replace basename&sed w/ zsh variable expansion syntax

`${var:t:h}` uses:

- `${var:t}` which acts as `basename`.

- `${var:r}` which removes the extension.

See http://zsh.sourceforge.net/Doc/Release/Expansion.html#Modifiers

aaronbieber/oh-my-zsh,aaronbieber/oh-my-zsh