Fix handling of whitespace.

Whitespace will no longer be removed from input lines, which fixes pasting
multiline strings containing end-of-line or beginning-of-line whitespace.

nix-repl.cc

@@ -178,14 +178,13 @@ bool NixRepl::getLine(string & input, const char * prompt)
 
         char * s = readline(prompt);
         if (!s) return false;
-        string line = chomp(string(s));
-        input.append(removeWhitespace(line));
+        input.append(s);
         input.push_back('\n');
-        free(s);
-        if (line != "") {
-            add_history(line.c_str());
+        if (!removeWhitespace(s).empty()) {
+            add_history(s);
             append_history(1, 0);
         }
+        free(s);
     }
 
     _isInterrupted = 0;