work-around a generics compilation issue

beacon_chain/private/helpers.nim

@@ -31,12 +31,7 @@ func shuffle*[T](values: seq[T], seed: Blake2_256_Digest): seq[T] =
     index = 0
   while index < values_count - 1:
     # Re-hash the `source` to obtain a new pattern of bytes.
-
-    # XXX: attempting to call undeclared routine: 'init'
-    # https://github.com/nim-lang/Nim/issues/8677
-    #
-    # mixin init? doesn't seem to be enough
-    #source = blake2_256.digest source.data
+    source = blake2_256.digest source.data
 
     # Iterate through the `source` bytes in 3-byte chunks.
     for pos in countup(0, 29, 3):

beacon_chain/validator.nim

@@ -8,7 +8,7 @@
 
 import
   options,
-  eth_common,
+  eth_common, nimcrypto/blake2,
   ./datatypes, ./private/helpers
 
 func min_empty_validator(validators: seq[ValidatorRecord], current_slot: uint64): Option[int] =