[devdoc] update example AST (JuliaLang#43150)

doc/src/devdocs/ast.md

@@ -53,8 +53,6 @@ call. Finally, chains of comparisons have their own special expression structure
 | `a&&b` | `(&& a b)` |
 | `x += 1` | `(+= x 1)` |
 | `a ? 1 : 2` | `(if a 1 2)` |
-| `a:b` | `(: a b)` |
-| `a:b:c` | `(: a b c)` |
 | `a,b` | `(tuple a b)` |
 | `a==b` | `(call == a b)` |
 | `1<i<=n` | `(comparison 1 < i <= n)` |
@@ -78,10 +76,10 @@ call. Finally, chains of comparisons have their own special expression structure
 | `[x y]` | `(hcat x y)` |
 | `[x y; z t]` | `(vcat (row x y) (row z t))` |
 | `[x;y;; z;t;;;]` | `(ncat 3 (nrow 2 (nrow 1 x y) (nrow 1 z t)))` |
-| `[x for y in z, a in b]` | `(comprehension x (= y z) (= a b))`  |
-| `T[x for y in z]` | `(typed_comprehension T x (= y z))`  |
+| `[x for y in z, a in b]` | `(comprehension (generator x (= y z) (= a b)))` |
+| `T[x for y in z]` | `(typed_comprehension T (generator x (= y z)))` |
 | `(a, b, c)` | `(tuple a b c)` |
-| `(a; b; c)` | `(block a (block b c))` |
+| `(a; b; c)` | `(block a b c)`  |
 
 ### Macros
 
@@ -130,11 +128,11 @@ instead of `:import`.
 Julia supports more number types than many scheme implementations, so not all numbers are represented
 directly as scheme numbers in the AST.
 
-| Input | AST |
-|:----------------------- |:------------------------------------------------------- |
-| `11111111111111111111` | `(macrocall @int128_str (null) "11111111111111111111")` |
-| `0xfffffffffffffffff` | `(macrocall @uint128_str (null) "0xfffffffffffffffff")` |
-| `1111...many digits...` | `(macrocall @big_str (null) "1111....")` |
+| Input | AST  |
+|:----------------------- |:-------------------------------------------------------- |
+| `11111111111111111111` | `(macrocall @int128_str nothing "11111111111111111111")` |
+| `0xfffffffffffffffff` | `(macrocall @uint128_str nothing "0xfffffffffffffffff")` |
+| `1111...many digits...` | `(macrocall @big_str nothing "1111....")` |
 
 ### Block forms
 
@@ -157,7 +155,7 @@ parses as:
 ```
 (if a (block (line 2) b)
  (elseif (block (line 3) c) (block (line 4) d)
- (block (line 5 e))))
+ (block (line 6 e))))
 ```
 
 A `while` loop parses as `(while condition body)`.