Libguestfs - Sep 2016 - [PATCH 2/2] dib: use remove_duplicates instead of own code

Simple code motion.
---
 mllib/common_utils.ml  | 9 +++++++++
 mllib/common_utils.mli | 6 ++++++
 v2v/utils.ml           | 9 ---------
 v2v/utils.mli          | 3 ---
 4 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/mllib/common_utils.ml b/mllib/common_utils.ml
index 81d8202..78618f5 100644
--- a/mllib/common_utils.ml
+++ b/mllib/common_utils.ml
@@ -297,6 +297,15 @@ let sort_uniq ?(cmp = Pervasives.compare) xs    let xs =
uniq ~cmp xs in
   xs
 
+let remove_duplicates xs +  let h = Hashtbl.create (List.length xs) in
+  let rec loop = function
+    | [] -> []
+    | x :: xs when Hashtbl.mem h x -> xs
+    | x :: xs -> Hashtbl.add h x true; x :: loop xs
+  in
+  loop xs
+
 let push_back xsp x = xsp := !xsp @ [x]
 let push_front x xsp = xsp := x :: !xsp
 let pop_back xsp diff --git a/mllib/common_utils.mli b/mllib/common_utils.mli
index 68c0d54..ad43345 100644
--- a/mllib/common_utils.mli
+++ b/mllib/common_utils.mli
@@ -147,6 +147,12 @@ val uniq : ?cmp:('a -> 'a -> int) ->
'a list -> 'a list
 val sort_uniq : ?cmp:('a -> 'a -> int) -> 'a list ->
'a list
 (** Sort and uniquify a list. *)
 
+val remove_duplicates : 'a list -> 'a list
+(** Remove duplicates from an unsorted list; useful when the order
+    of the elements matter.
+
+    Please use [sort_uniq] when the order does not matter. *)
+
 val push_back : 'a list ref -> 'a -> unit
 val push_front : 'a -> 'a list ref -> unit
 val pop_back : 'a list ref -> 'a
diff --git a/v2v/utils.ml b/v2v/utils.ml
index d1ddee7..fb0b802 100644
--- a/v2v/utils.ml
+++ b/v2v/utils.ml
@@ -81,15 +81,6 @@ let compare_app2_versions app1 app2        compare_version
app1.Guestfs.app2_release app2.Guestfs.app2_release
   )
 
-let remove_duplicates xs -  let h = Hashtbl.create (List.length xs) in
-  let rec loop = function
-    | [] -> []
-    | x :: xs when Hashtbl.mem h x -> xs
-    | x :: xs -> Hashtbl.add h x true; x :: loop xs
-  in
-  loop xs
-
 let du filename    (* There's no OCaml binding for st_blocks, so run
coreutils 'du'. *)
   let cmd diff --git a/v2v/utils.mli b/v2v/utils.mli
index 97d98ff..2bd1329 100644
--- a/v2v/utils.mli
+++ b/v2v/utils.mli
@@ -46,9 +46,6 @@ val find_uefi_firmware : string -> Uefi.uefi_firmware
 val compare_app2_versions : Guestfs.application2 -> Guestfs.application2
-> int
 (** Compare two app versions. *)
 
-val remove_duplicates : 'a list -> 'a list
-(** Remove duplicates from a list. *)
-
 val du : string -> int64
 (** Return the true size of a file in bytes, including any wasted
     space caused by internal fragmentation (the overhead of using
-- 
2.7.4

Use a common function to remove duplicates in an unsorted list.

Just refactoring, with no behaviour change.
---
 dib/cmdline.ml | 2 +-
 dib/utils.ml   | 4 ----
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/dib/cmdline.ml b/dib/cmdline.ml
index 1fd6c71..144e5a7 100644
--- a/dib/cmdline.ml
+++ b/dib/cmdline.ml
@@ -107,7 +107,7 @@ read the man page virt-dib(1).
 
   let formats = ref ["qcow2"] in
   let set_format arg -    let fmts = remove_dups (String.nsplit ","
arg) in
+    let fmts = remove_duplicates (String.nsplit "," arg) in
     List.iter (
       function
       | "qcow2" | "tar" | "raw" | "vhd"
| "docker" -> ()
diff --git a/dib/utils.ml b/dib/utils.ml
index a2046cb..3df5171 100644
--- a/dib/utils.ml
+++ b/dib/utils.ml
@@ -91,10 +91,6 @@ let digit_prefix_compare a b  let do_mkdir dir    mkdir_p dir
0o755
 
-let rec remove_dups = function
-  | [] -> []
-  | x :: xs -> x :: (remove_dups (List.filter ((<>) x) xs))
-
 let require_tool tool    try ignore (which tool)
   with Executable_not_found tool ->
-- 
2.7.4

On Fri, Sep 23, 2016 at 06:05:25PM +0200, Pino Toscano
wrote:
> Use a common function to remove duplicates in an unsorted list.
> 
> Just refactoring, with no behaviour change.
Except it's no longer O(n^2) :-)

ACK series.

Rich.
> ---
>  dib/cmdline.ml | 2 +-
>  dib/utils.ml   | 4 ----
>  2 files changed, 1 insertion(+), 5 deletions(-)
> 
> diff --git a/dib/cmdline.ml b/dib/cmdline.ml
> index 1fd6c71..144e5a7 100644
> --- a/dib/cmdline.ml
> +++ b/dib/cmdline.ml
> @@ -107,7 +107,7 @@ read the man page virt-dib(1).
>  
>    let formats = ref ["qcow2"] in
>    let set_format arg > -    let fmts = remove_dups (String.nsplit
"," arg) in
> +    let fmts = remove_duplicates (String.nsplit "," arg) in
>      List.iter (
>        function
>        | "qcow2" | "tar" | "raw" |
"vhd" | "docker" -> ()
> diff --git a/dib/utils.ml b/dib/utils.ml
> index a2046cb..3df5171 100644
> --- a/dib/utils.ml
> +++ b/dib/utils.ml
> @@ -91,10 +91,6 @@ let digit_prefix_compare a b >  let do_mkdir dir >
mkdir_p dir 0o755
>  
> -let rec remove_dups = function
> -  | [] -> []
> -  | x :: xs -> x :: (remove_dups (List.filter ((<>) x) xs))
> -
>  let require_tool tool >    try ignore (which tool)
>    with Executable_not_found tool ->
> -- 
> 2.7.4
> 
> _______________________________________________
> Libguestfs mailing list
> Libguestfs@redhat.com
> https://www.redhat.com/mailman/listinfo/libguestfs
-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org