* Option --argstr for passing string arguments easily. (NIX-75)

src/libexpr/common-opts.cc

@@ -0,0 +1,32 @@
+#include "common-opts.hh"
+#include "../libmain/shared.hh"
+#include "util.hh"
+#include "parser.hh"
+
+
+namespace nix {
+
+
+bool parseOptionArg(const string & arg, Strings::iterator & i,
+    const Strings::iterator & argsEnd, EvalState & state,
+    ATermMap & autoArgs)
+{
+    if (arg != "--arg" && arg != "--argstr") return false;
+
+    UsageError error(format("`%1%' requires two arguments") % arg);
+    
+    if (i == argsEnd) throw error;
+    string name = *i++;
+    if (i == argsEnd) throw error;
+    string value = *i++;
+    
+    Expr e = arg == "--arg"
+        ? parseExprFromString(state, value, absPath("."))
+        : makeStr(value);
+    autoArgs.set(toATerm(name), e);
+    
+    return true;
+}
+
+ 
+}