Pretty flashy :-) I like how it told me to use () when I tried typing $(), and the autocompletion is quite impressive.

However, how do you work around the lack of <() and >()? E.g. if I want to do the equivalent of

    $ diff <(xzcat foo.xz) <(xzcat bar.xz)

?

EDIT: nevermind, I see the fish version is

    $ diff (xzcat foo.xz|psub) (xzcat bar.xz|psub)

which actually does the mkfifo dance for you :-)