zsh alias with default argument, but also overridable

I currently have a zsh alias setup like so.

alias e="subl"

This lets me e somedir to open up a directory in SublimeText. or e . to open up the current directory.

However, I would like to be able set . to be the default argument, or I can optionally pass in another directory.

So e should expand to subl .

And e somedir should expand to subl somedir

How exactly does one set this up? Is an alias even what I need here?

Solution 1:

I would use a function:

function e() {
    if [ "$1" != "" ]
    then
        subl $1
    else
        subl .
    fi
}

adding it to .profile