Allow ignoring responses at transport layer

Future versions may make this async.

autoload/fireplace/nrepl.vim

@@ -48,7 +48,7 @@ function! s:nrepl_close() dict abort
   if has_key(self, 'session')
     try
       unlet! g:fireplace_nrepl_sessions[self.session]
-      call self.message({'op': 'close'}, 'fireplace#nrepl#ignore')
+      call self.message({'op': 'close'}, 'ignore')
     catch
     finally
       unlet self.session
@@ -136,7 +136,7 @@ function! s:nrepl_eval(expr, ...) dict abort
     let response = self.process(msg)
   catch /^Vim:Interrupt$/
     if has_key(msg, 'session')
-      call self.message({'op': 'interrupt', 'session': msg.session, 'interrupt-id': msg.id}, 'fireplace#nrepl#ignore')
+      call self.message({'op': 'interrupt', 'session': msg.session, 'interrupt-id': msg.id}, 'ignore')
     endif
     throw 'Clojure: Interrupt'
   endtry
@@ -194,9 +194,6 @@ function! fireplace#nrepl#callback(body, type, fn)
   call call(a:fn, [response])
 endfunction
 
-function! fireplace#nrepl#ignore(...) abort
-endfunction
-
 function! s:nrepl_call(msg, ...) dict abort
   let terms = a:0 ? a:1 : ['done']
   let sels = a:0 > 1 ? a:2 : {}

autoload/nrepl/fireplace_connection.vim

@@ -103,10 +103,10 @@ endfunction
 function! s:nrepl_transport_call(msg, terms, sels, ...) dict abort
   let payload = nrepl#fireplace_connection#bencode(a:msg)
   let response = self.dispatch('call', payload, a:terms, a:sels)
-  if a:0
+  if !a:0
-    return map(response, 'fireplace#nrepl#callback(v:val, "synchronous", a:1)')
-  else
     return response
+  elseif a:1 !=# 'ignore'
+    return map(response, 'fireplace#nrepl#callback(v:val, "synchronous", a:1)')
   endif
 endfunction