[__david__]

Well, it's about 400 lines total. Roughly 40% of that is PATH handling functions: add_to, append_to, replace_in, remove_from, prefix and unprefix. They're used like:

    add_to PATH /usr/sbin

prefix and unprefix are a macro for a bunch of standard replace_in/remove_froms:

    prefix() {
        replace_in PATH "$1/bin"
        replace_in PATH "$1/sbin"
        replace_in PATH "$1/lib/ccache"
        replace_in MANPATH "$1/share/man"
        replace_in MANPATH "$1/man"
        replace_in PKG_CONFIG_PATH "$1/lib/pkgconfig"
    ...etc.

So that later I can do stuff like:

    prefix /usr/local
    prefix /usr/local/brew
    prefix /usr/local/ports

...All of which are managed by different package managers (stow, brew, ports).

All that stuff is the part I optimized so that it only uses bash built-ins and never execs. Converting that away from sed/perl shaved about 8 seconds off my startup time (it's now so fast I don't notice it).

The next 20% is interactive stuff. Setting up the prompt, aliases, stty, etc. This is generally more complicated than it technically needs to be because it's cross platform so it'll run on any unix-y thing with no changes.

Then remaining 40% is a big chunk of shell functions that are mostly unused in my day-to-day life, but kept there to jog my memory if I need to do a certain task.

That adds up to 100%, but it's also worth noting that 27% of that is blank lines and comments.