I don't know if this helps at all but you can use `export FOO=bar` in Fish, and the prefixing a line with an envvar should work the same as in Bash etc. like `F

I don't know if this helps at all but you can use `export FOO=bar` in Fish, and the prefixing a line with an envvar should work the same as in Bash etc. like `FOO=bar echo $FOO`