How to set workDir for std.process.execute ?

[KrzaQ via Digitalmars-d-learn]

Hello,

I'm trying to follow the documentation: 
http://dlang.org/phobos/std_process.html#.execute

Unfortunately, the following code gives me a compiler error:
class Probator
{
        char[] dir;

        this(const char[] dir){
                this.dir = dir.dup;
        }

        int revision(){
                import std.process;
                import std.conv;

                const char[] workDir = "~".dup;
		auto p = std.process.execute(["svnversion", dir], null, 
Config.none, size_t.max, workDir);
                if(p.status == 0){
                        return to!int(p.output);
                }else{
                        throw new Exception(p.output);
                }
        }
}

error:
/d629/f876.d(15): Error: function std.process.execute 
(const(char[][]) args, const(immutable(char)[][string]) env = 
null, Config config = cast(Config)0, ulong maxOutput = 
18446744073709551615LU) is not callable using argument types 
(const(char)[][], typeof(null), Config, ulong, const(char[]))

It's as if the implementation didn't expect the last argument.