You are currently looking at the v11.0 docs, which are still a work in progress. If you miss anything, you may find it in the older v10.0 docs here.
Reserved Keywords
Note: Some of these words are reserved purely for backward compatibility.
If you need to use one of these names as binding and/or field name, see Use Illegal Identifier Names.
and
as
assert
constraint
else
exception
external
false
for
if
in
include
lazy
let
module
mutable
of
open
rec
switch
true
try
type
when
while
with