change concurrency library to use new catch usage

contrib/concurrency/concurrency-examples.factor

@@ -128,12 +128,12 @@ M: crash-command run-rpc-command ( command -- shutdown? result )
 : (robust-rpc-server) ( worker -- )
   [
     receive over send
-  ] [
-    [  
-      "Worker died, Starting a new worker" print
-      drop [ handle-rpc-message ] spawn-linked-server
-    ] when
-  ] catch 
+  ] 
+  catch 
+  [  
+    "Worker died, Starting a new worker" print
+    drop [ handle-rpc-message ] spawn-linked-server
+  ] when
   (robust-rpc-server) ;
   
 : robust-rpc-server ( -- process )

contrib/concurrency/concurrency-tests.factor

@@ -164,8 +164,7 @@ USING: kernel concurrency concurrency-examples threads vectors
     ] spawn-link drop
     receive
   ] 
-  [
-  ] catch
+  catch
 ] unit-test 
 
 [ 50 ] [

contrib/concurrency/concurrency.factor

@@ -209,7 +209,7 @@ TUPLE: linked-exception error ;
   #! Same as spawn but if the quotation throws an error that
   #! is uncaught, that error gets propogated to the process
   #! performing the spawn-link.
-  [ [ [ rethrow-linked ] when* ] catch ] cons
+  [ catch [ rethrow-linked ] when* ] cons
   [ in-thread ] self make-linked-process [ with-process ] over slip ;
 
 #! A common operation is to send a message to a process containing

contrib/concurrency/concurrency.html

@@ -349,9 +349,9 @@ can catch it:</p>
     "This will not print" print
   ] spawn-link drop
   receive
-] [ 
-  [ "Exception caught." print ] when
-] catch</span>
+] 
+catch [ "Exception caught." print ] when
+</span>
   => "Exception caught."
 </pre>
 <p>Exceptions are only raised in the parent when the parent does a
@@ -427,12 +427,12 @@ worker:</p>
   [
     #! Forward all messages to worker
     receive over send
-  ] [
-    [  
-      "Worker died, Starting a new worker" print
-      drop [ handle-rpc-message ] spawn-linked-server
-    ] when
-  ] catch 
+  ] 
+  catch 
+  [  
+    "Worker died, Starting a new worker" print
+    drop [ handle-rpc-message ] spawn-linked-server
+  ] when
   (robust-rpc-server) ;
   
 : robust-rpc-server ( -- process )