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There are two kinds of casts for array values:
For example, we have seen that the type of an array literal is always
bounded by a constant number of elements. Thus the type of
[1,2,3]
is int[3]
.
We could cast the value above to an unbounded array type by doing:
[1,2,3] as int[]
Or to an array bounded by size:
[1,2,3] as int[12#B]
Of course trying to cast an array value to a type for which the bounding restrictions will fail. This will give you a compile-time error:
[1,2,3] as int[4]
And this will result in a run-time error:
(poke) [1,2,3] as int[13#B] unhandled conversion error exception
Now let’s see how Poke reinterprets integral arrays as integers:
(poke) [0xdeUB,0xadUB] as uint16 0xdeadUH (poke) [0xdeUB,0xadUB,0UB] as int 0xdead00
Trying to cast an array with a size larger than 64-bit will result in an error:
(poke) [1,2,3] as int unhandled conversion error exception arrays bigger than 64-bit cannot be casted to integral types
It also works for nested arrays and arrays of integral structs (See Integral Structs):
(poke) type Foo = struct uint { int16 hi; int16 lo; }; (poke) [[Foo{ hi=0xdeadH, lo=0xbeefH}],[Foo{}]] as ulong 0xdeadbeef00000000UL
The way it works is like putting all array elements in an
uint<64>
number and then casting that number to the
destination integral type.
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