7:56 a.m.
In OCaml >= 4.02, match can catch exceptions.
Old code looks like:
try
match expr with
| patt1 -> (* handle patt1 *)
| patt2 -> ...
with
exn -> (* handle exception *)
New code looks like:
match expr with
| patt1 -> (* handle patt1 *)
| patt2 -> ...
| exception exn -> (* handle exception *)
*NB* These are not exactly equivalent, since in the old code an
exception thrown in the ‘(* handle patt1 *)’ code would be caught by
the exception handler, but this does NOT happen in the new code.
Therefore caution is advised when rewriting code.
See also:
https://blog.janestreet.com/pattern-matching-and-exception-handling-unite/
---
builder/sources.ml | 30 ++++++++++++------------------
common/mlstdutils/std_utils.ml | 8 +++-----
daemon/inspect_fs_unix_fstab.ml | 10 ++++------
daemon/inspect_utils.ml | 18 ++++++------------
v2v/parse_vmx.ml | 10 ++++------
5 files changed, 29 insertions(+), 47 deletions(-)
diff --git a/builder/sources.ml b/builder/sources.ml
index d6de15968..2710b5203 100644
--- a/builder/sources.ml
+++ b/builder/sources.ml
@@ -64,25 +64,19 @@ let parse_conf file =
Utils.No_Key
) in
let proxy =
- try
- (match (List.assoc ("proxy", None) fields) with
- | "no" | "off" -> Curl.UnsetProxy
- | "system" -> Curl.SystemProxy
- | _ as proxy -> Curl.ForcedProxy proxy
- )
- with
- Not_found -> Curl.SystemProxy in
+ match List.assoc ("proxy", None) fields with
+ | "no" | "off" -> Curl.UnsetProxy
+ | "system" -> Curl.SystemProxy
+ | _ as proxy -> Curl.ForcedProxy proxy
+ | exception Not_found -> Curl.SystemProxy in
let format =
- try
- (match (List.assoc ("format", None) fields) with
- | "native" | "" -> FormatNative
- | "simplestreams" -> FormatSimpleStreams
- | fmt ->
- debug "unknown repository type '%s' in %s, skipping it"
fmt file;
- invalid_arg fmt
- )
- with
- Not_found -> FormatNative in
+ match List.assoc ("format", None) fields with
+ | "native" | "" -> FormatNative
+ | "simplestreams" -> FormatSimpleStreams
+ | fmt ->
+ debug "unknown repository type '%s' in %s, skipping it"
fmt file;
+ invalid_arg fmt
+ | exception Not_found -> FormatNative in
{
name = n; uri = uri; gpgkey = gpgkey; proxy = proxy;
format = format;
diff --git a/common/mlstdutils/std_utils.ml b/common/mlstdutils/std_utils.ml
index 37eef0348..0f691db0d 100644
--- a/common/mlstdutils/std_utils.ml
+++ b/common/mlstdutils/std_utils.ml
@@ -600,11 +600,9 @@ let may f = function
type ('a, 'b) maybe = Either of 'a | Or of 'b
let protect ~f ~finally =
- let r =
- try Either (f ())
- with exn -> Or exn in
- finally ();
- match r with Either ret -> ret | Or exn -> raise exn
+ match f () with
+ | ret -> finally (); ret
+ | exception exn -> finally (); raise exn
let failwithf fs = ksprintf failwith fs
diff --git a/daemon/inspect_fs_unix_fstab.ml b/daemon/inspect_fs_unix_fstab.ml
index e3c7fd1cd..16c5d5e7c 100644
--- a/daemon/inspect_fs_unix_fstab.ml
+++ b/daemon/inspect_fs_unix_fstab.ml
@@ -317,13 +317,11 @@ and resolve_fstab_device spec md_map os_type =
* This makes it impossible to reverse those paths directly, so
* we have implemented lvm_canonical_lv_name in the daemon.
*)
- try
- match Lvm.lv_canonical spec with
- | None -> Mountable.of_device spec
- | Some device -> Mountable.of_device device
- with
+ match Lvm.lv_canonical spec with
+ | None -> Mountable.of_device spec
+ | Some device -> Mountable.of_device device
(* Ignore devices that don't exist. (RHBZ#811872) *)
- | Unix.Unix_error (Unix.ENOENT, _, _) -> default
+ | exception Unix.Unix_error (Unix.ENOENT, _, _) -> default
)
else if PCRE.matches re_xdev spec then (
diff --git a/daemon/inspect_utils.ml b/daemon/inspect_utils.ml
index ef45ba9ee..94f728e3c 100644
--- a/daemon/inspect_utils.ml
+++ b/daemon/inspect_utils.ml
@@ -129,20 +129,14 @@ and aug_rm_noerrors aug path =
with Augeas.Error _ -> 0
let is_file_nocase path =
- let path =
- try Some (Realpath.case_sensitive_path path)
- with _ -> None in
- match path with
- | None -> false
- | Some path -> Is.is_file path
+ match Realpath.case_sensitive_path path with
+ | path -> Is.is_file path
+ | exception _ -> false
and is_dir_nocase path =
- let path =
- try Some (Realpath.case_sensitive_path path)
- with _ -> None in
- match path with
- | None -> false
- | Some path -> Is.is_dir path
+ match Realpath.case_sensitive_path path with
+ | path -> Is.is_dir path
+ | exception _ -> false
(* Rather hairy test for "is a partition", taken directly from
* the old C inspection code. XXX fix function and callers
diff --git a/v2v/parse_vmx.ml b/v2v/parse_vmx.ml
index 3c72527b9..2b8a86a14 100644
--- a/v2v/parse_vmx.ml
+++ b/v2v/parse_vmx.ml
@@ -338,12 +338,10 @@ and insert vmx value = function
StringMap.add k (Key value) vmx
| ns :: path ->
let v =
- try
- (match StringMap.find ns vmx with
- | Namespace vmx -> Some vmx
- | Key _ -> None
- )
- with Not_found -> None in
+ match StringMap.find ns vmx with
+ | Namespace vmx -> Some vmx
+ | Key _ -> None
+ | exception Not_found -> None in
let v =
match v with
| None ->
--
2.13.2