X-Git-Url: https://git.xandkar.net/?a=blobdiff_plain;f=src%2Fhope_result.erl;h=44f3ddd58b92e21ba0941e4d274b31d495fd68c9;hb=70cf8e86a06d8721fcc8b658bb2be1f7b401326f;hp=06f1eebd43f279d75d7f309fb55e77664b5a566c;hpb=3b156801097bcd07272f1db3a62a675495fa9d77;p=hope.git

diff --git a/src/hope_result.erl b/src/hope_result.erl
index 06f1eeb..44f3ddd 100644
--- a/src/hope_result.erl
+++ b/src/hope_result.erl
@@ -1,11 +1,13 @@
 -module(hope_result).
 
+
 -export_type(
     [ t/2
     ]).
 
 -export(
     [ pipe/2
+    , lift_exn/1
     ]).
 
 
@@ -15,9 +17,33 @@
     .
 
 
-pipe([]    , X) -> X;
+-spec pipe([F], X) ->
+    t(Ok, Error)
+    when X     :: any()
+       , Ok    :: any()
+       , Error :: any()
+       , F     :: fun((X) -> t(Ok, Error))
+       .
+pipe([], X) ->
+    {ok, X};
 pipe([F|Fs], X) ->
     case F(X)
     of  {error, _}=E -> E
     ;   {ok, Y}      -> pipe(Fs, Y)
     end.
+
+-spec lift_exn(F) -> G
+    when F     :: fun((A)-> B)
+       , G     :: fun((A)-> t(B, {Class, Reason :: any()}))
+       , Class :: error
+                | exit
+                | throw
+       .
+lift_exn(F) when is_function(F, 1) ->
+    fun(X) ->
+        try
+            {ok, F(X)}
+        catch Class:Reason ->
+            {error, {Class, Reason}}
+        end
+    end.