Fix use of old row tail syntax in manual
@@ -356,7 +356,7 @@ we can substitute a parameter for a whole sequence of field declarations, also
referred to as rows:
```nickel
-(let addTotal: forall a b. {total: Num | a} -> {total: Num | b} -> Num
+(let addTotal: forall a b. {total: Num ; a} -> {total: Num ; b} -> Num
= fun r1 r2 => r1.total + r2.total in
let r1 = {jan = 200, feb = 300, march = 10, total = jan + feb} in
let r2 = {aug = 50, sept = 20, total = aug + sept} in
@@ -372,18 +372,18 @@ Result:
{partial1 = 570, partial2 = 1770}
```
-In the type of `addTotal`, the part `{total: Num | a}` expresses exactly what we
+In the type of `addTotal`, the part `{total: Num ; a}` expresses exactly what we
wanted: the argument must have a field `total: Num`, but the *tail* (the rest of
the record type) is polymorphic, and `a` may be substituted for arbitrary fields
(such as `jan: Num, feb: Num`). We used two different generic parameters `a` and
`b`, to express that the tails of the arguments may differ. If we used `a` in
-both places, as in `forall a. {total: Num | a} -> {total: Num | a} -> Num`, we
+both places, as in `forall a. {total: Num ; a} -> {total: Num ; a} -> Num`, we
could still write `addTotal {total = 1, foo = 1} {total = 2, foo = 2}` but not
`addTotal {total = 1, foo = 1} {total = 2, bar = 2}`. Using distinct parameters
`a` and `b` gives us maximum flexibility.
What comes before the tail may include several fields, is in e.g. `forall a.
-{total: Num, subtotal: Num | a} -> Num`.
+{total: Num, subtotal: Num ; a} -> Num`.
<!-- Note that row polymorphism also works with enums, with the same intuition of a -->
<!-- tail that can be substituted for something else. For example: -->
