diff --git a/lib/array.fs b/lib/array.fs
index e7fc5b7..12d32c4 100644
--- a/lib/array.fs
+++ b/lib/array.fs
@@ -5,7 +5,6 @@
 
 private{
 
-( === Allocation strategy === )
 defined? array-alloc-strategy [unless]
 
 \ Compute new capacity
@@ -21,8 +20,6 @@ struct
     int% field array>capa
 end-struct array%
 
-s" Index out of range" exception constant OUT-OF-RANGE export
-
 \ Allocate array with capacity
 : allocate-array ( n capa -- arr )
     array% %allocate throw
diff --git a/lib/core.fs b/lib/core.fs
index 297ee6d..03652fa 100644
--- a/lib/core.fs
+++ b/lib/core.fs
@@ -16,6 +16,9 @@ s" Invalid argument" exception constant INVALID-ARGUMENT
     unless INVALID-ARGUMENT throw then
 ;
 
+( === Builtin Exceptions === )
+s" Index out of range" exception constant OUT-OF-RANGE export
+
 defined? roll [unless]
     : roll ( w[n-1] ... w0 n -- w0 w[n-2] ... w0 w[n-1] )
         dup 0<= if drop else swap >r 1- recurse r> swap then