feat(users/sterni/nix/flow): add switch conditional r/2269

switch would probably otherwise be called match, but has been renamed so
it isn't confused with string.match and the enum matching capabilities
yants has.

It implements the closest to pattern matching nix can come which is
still flexible enough to not be painful: Syntactically it works like
cond, but is given a value. Instead of booleans it checks passed
predicates or equality if simple values are passed. Both types of checks
can be mixed.

Change-Id: I40f000979cfd469316e15fd58d6c3a80312c1cc4
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2589
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>

0 files changed, 0 insertions, 0 deletions