Monadic @ (type)

Returns internal type id of an argument.

Syntax: @x; @[x]

Avoid relying on these ids in production!

o)@1
80
o)@"s"
46400
o)@([]a:1;b:"a")
126988
o)d:`a`c!(1;2)
a| 1
c| 2
o)@d
126992
o)@flip d
126988
o)