diff --git a/extra/io/sockets/impl/impl.factor b/extra/io/sockets/impl/impl.factor
index 5b0790ca2d..498430fdbc 100755
--- a/extra/io/sockets/impl/impl.factor
+++ b/extra/io/sockets/impl/impl.factor
@@ -90,7 +90,7 @@ M: inet6 parse-sockaddr
         { [ dup AF_INET = ] [ T{ inet4 } ] }
         { [ dup AF_INET6 = ] [ T{ inet6 } ] }
         { [ dup AF_UNIX = ] [ T{ local } ] }
-        { [ t ] [ f ] }
+        [ f ]
     } cond nip ;
 
 M: f parse-sockaddr nip ;
diff --git a/extra/io/unix/files/files.factor b/extra/io/unix/files/files.factor
index 39c18b4601..ed54eb26f3 100755
--- a/extra/io/unix/files/files.factor
+++ b/extra/io/unix/files/files.factor
@@ -76,16 +76,16 @@ M: unix copy-file ( from to -- )
     2bi ;
 
 : stat>type ( stat -- type )
-    stat-st_mode {
-        { [ dup S_ISREG  ] [ +regular-file+     ] }
-        { [ dup S_ISDIR  ] [ +directory+        ] }
-        { [ dup S_ISCHR  ] [ +character-device+ ] }
-        { [ dup S_ISBLK  ] [ +block-device+     ] }
-        { [ dup S_ISFIFO ] [ +fifo+             ] }
-        { [ dup S_ISLNK  ] [ +symbolic-link+    ] }
-        { [ dup S_ISSOCK ] [ +socket+           ] }
-        { [ t            ] [ +unknown+          ] }
-    } cond nip ;
+    stat-st_mode S_IFMT bitand {
+        { S_IFREG [ +regular-file+ ] }
+        { S_IFDIR [ +directory+ ] }
+        { S_IFCHR [ +character-device+ ] }
+        { S_IFBLK [ +block-device+ ] }
+        { S_IFIFO [ +fifo+ ] }
+        { S_IFLNK [ +symbolic-link+ ] }
+        { S_IFSOCK [ +socket+ ] }
+        [ drop +unknown+ ]
+    } case ;
 
 : stat>file-info ( stat -- info )
     {
diff --git a/extra/io/unix/launcher/launcher.factor b/extra/io/unix/launcher/launcher.factor
index 82852f6311..2c1e6261c0 100755
--- a/extra/io/unix/launcher/launcher.factor
+++ b/extra/io/unix/launcher/launcher.factor
@@ -55,7 +55,7 @@ USE: unix
         { [ pick string? ] [ redirect-file ] }
         { [ pick +closed+ eq? ] [ redirect-closed ] }
         { [ pick +inherit+ eq? ] [ redirect-closed ] }
-        { [ t ] [ redirect-stream ] }
+        [ redirect-stream ]
     } cond ;
 
 : ?closed dup +closed+ eq? [ drop "/dev/null" ] when ;
diff --git a/extra/io/windows/nt/backend/backend.factor b/extra/io/windows/nt/backend/backend.factor
index 822973b85b..3c490b780c 100755
--- a/extra/io/windows/nt/backend/backend.factor
+++ b/extra/io/windows/nt/backend/backend.factor
@@ -39,7 +39,7 @@ M: winnt add-completion ( handle -- )
         GetLastError {
             { [ dup expected-io-error? ] [ 2drop t ] }
             { [ dup eof? ] [ drop t swap set-port-eof? f ] }
-            { [ t ] [ (win32-error-string) throw ] }
+            [ (win32-error-string) throw ]
         } cond
     ] [
         drop t
diff --git a/extra/io/windows/nt/files/files.factor b/extra/io/windows/nt/files/files.factor
index 3232ab6ff3..f2615b67de 100755
--- a/extra/io/windows/nt/files/files.factor
+++ b/extra/io/windows/nt/files/files.factor
@@ -25,7 +25,7 @@ M: winnt root-directory? ( path -- ? )
           { [ dup length 2 = ] [ dup second CHAR: : = ] } && nip ] [
             t
         ] }
-        { [ t ] [ f ] }
+        [ f ]
     } cond nip ;
 
 ERROR: not-absolute-path ;
diff --git a/extra/io/windows/nt/launcher/launcher.factor b/extra/io/windows/nt/launcher/launcher.factor
index 97de248d24..f57902608f 100755
--- a/extra/io/windows/nt/launcher/launcher.factor
+++ b/extra/io/windows/nt/launcher/launcher.factor
@@ -55,7 +55,7 @@ IN: io.windows.nt.launcher
         { [ pick +inherit+ eq? ] [ redirect-inherit ] }
         { [ pick +closed+ eq? ] [ redirect-closed ] }
         { [ pick string? ] [ redirect-file ] }
-        { [ t ] [ redirect-stream ] }
+        [ redirect-stream ]
     } cond ;
 
 : default-stdout ( args -- handle )
diff --git a/extra/io/windows/nt/monitors/monitors.factor b/extra/io/windows/nt/monitors/monitors.factor
index 164b529b61..87e6280118 100755
--- a/extra/io/windows/nt/monitors/monitors.factor
+++ b/extra/io/windows/nt/monitors/monitors.factor
@@ -58,13 +58,13 @@ M: winnt <monitor> ( path recursive? -- monitor )
 
 : parse-action ( action -- changed )
     {
-        { [ dup FILE_ACTION_ADDED = ] [ +add-file+ ] }
-        { [ dup FILE_ACTION_REMOVED = ] [ +remove-file+ ] }
-        { [ dup FILE_ACTION_MODIFIED = ] [ +modify-file+ ] }
-        { [ dup FILE_ACTION_RENAMED_OLD_NAME = ] [ +rename-file+ ] }
-        { [ dup FILE_ACTION_RENAMED_NEW_NAME = ] [ +rename-file+ ] }
-        { [ t ] [ +modify-file+ ] }
-    } cond nip ;
+        { \ FILE_ACTION_ADDED [ +add-file+ ] }
+        { \ FILE_ACTION_REMOVED [ +remove-file+ ] }
+        { \ FILE_ACTION_MODIFIED [ +modify-file+ ] }
+        { \ FILE_ACTION_RENAMED_OLD_NAME [ +rename-file+ ] }
+        { \ FILE_ACTION_RENAMED_NEW_NAME [ +rename-file+ ] }
+        [ drop +modify-file+ ]
+    } case ;
 
 : memory>u16-string ( alien len -- string )
     [ memory>byte-array ] keep 2/ c-ushort-array> >string ;