diff --git a/basis/struct-arrays/struct-arrays-docs.factor b/basis/struct-arrays/struct-arrays-docs.factor
index 7b49d6ef42..175b2e2783 100644
--- a/basis/struct-arrays/struct-arrays-docs.factor
+++ b/basis/struct-arrays/struct-arrays-docs.factor
@@ -7,11 +7,11 @@ $nl
 "The " { $slot "underlying" } " slot holds a " { $link c-ptr } " with the raw data. This pointer can be passed to C functions." } ;
 
 HELP: <struct-array>
-{ $values { "length" integer } { "c-type" string } { "struct-array" struct-array } }
-{ $description "Creates a new array for holding values of the specified C type." } ;
+{ $values { "length" integer } { "struct-class" struct-class } { "struct-array" struct-array } }
+{ $description "Creates a new array for holding values of the specified struct type." } ;
 
 HELP: <direct-struct-array>
-{ $values { "alien" c-ptr } { "length" integer } { "c-type" string } { "struct-array" struct-array } }
+{ $values { "alien" c-ptr } { "length" integer } { "struct-class" struct-class } { "struct-array" struct-array } }
 { $description "Creates a new array for holding values of the specified C type, backed by the memory at " { $snippet "alien" } "." } ;
 
 HELP: struct-array-on
diff --git a/basis/struct-arrays/struct-arrays.factor b/basis/struct-arrays/struct-arrays.factor
index cc34072d2c..3adc4496ee 100755
--- a/basis/struct-arrays/struct-arrays.factor
+++ b/basis/struct-arrays/struct-arrays.factor
@@ -5,9 +5,6 @@ classes classes.struct kernel libc math parser sequences
 sequences.private words fry memoize compiler.units ;
 IN: struct-arrays
 
-: c-type-struct-class ( c-type -- class )
-    c-type boxed-class>> ; foldable
-
 TUPLE: struct-array
 { underlying c-ptr read-only }
 { length array-capacity read-only }
@@ -15,35 +12,36 @@ TUPLE: struct-array
 { class read-only }
 { ctor read-only } ;
 
-M: struct-array length length>> ; inline
-M: struct-array byte-length [ length>> ] [ element-size>> ] bi * ; inline
+<PRIVATE
 
 : (nth-ptr) ( i struct-array -- alien )
     [ element-size>> * >fixnum ] [ underlying>> ] bi <displaced-alien> ; inline
 
+: (struct-element-constructor) ( struct-class -- word )
+    [
+        "struct-array-ctor" f <word>
+        [ swap '[ _ memory>struct ] (( alien -- object )) define-inline ] keep
+    ] with-compilation-unit ;
+
+! Foldable memo word. This is an optimization; by precompiling a
+! constructor for array elements, we avoid memory>struct's slow path.
+MEMO: struct-element-constructor ( struct-class -- word )
+    (struct-element-constructor) ; foldable
+
+PRIVATE>
+
+M: struct-array length length>> ; inline
+
+M: struct-array byte-length [ length>> ] [ element-size>> ] bi * ; inline
+
 M: struct-array nth-unsafe
     [ (nth-ptr) ] [ ctor>> ] bi execute( alien -- object ) ; inline
 
 M: struct-array set-nth-unsafe
     [ (nth-ptr) swap ] [ element-size>> ] bi memcpy ; inline
 
-: (struct-element-constructor) ( c-type -- word )
-    [
-        "struct-array-ctor" f <word>
-        [
-            swap dup struct-class?
-            [ '[ _ memory>struct ] [ ] like ] [ drop [ ] ] if
-            (( alien -- object )) define-inline
-        ] keep
-    ] with-compilation-unit ;
-
-! Foldable memo word. This is an optimization; by precompiling a
-! constructor for array elements, we avoid memory>struct's slow path.
-MEMO: struct-element-constructor ( c-type -- word )
-    (struct-element-constructor) ; foldable
-
-: <direct-struct-array> ( alien length c-type -- struct-array )
-    [ heap-size ] [ c-type-struct-class ] [ struct-element-constructor ]
+: <direct-struct-array> ( alien length struct-class -- struct-array )
+    [ heap-size ] [ ] [ struct-element-constructor ]
     tri struct-array boa ; inline
 
 M: struct-array new-sequence