The optional arguments are keyword arguments.
split(
"something},1",
"}";
limit=0,
keepempty=true
)
In a single line, you could also write one of the following.
split("something},1", "}"; limit=0, keepempty=true)
split("something},1", "}", limit=0, keepempty=true)
All the arguments past the optional ; must be keyword arguments.