Question

I would like to use IronRuby with the ERB system to parse .erb format files and get the output.

In ruby this would be like:

require "erb"
erbContent = "..."
return ERB.new(erbContent,0,"%<>").result

But this just doesnt work in my IronRuby project. I get an exception about the erb file being missing… so I guess this is a libraries issue. I then initiated my Ruby engine with the paths to my IronRuby directories, which then throws a different exception:

allocator undefined for System::String

Answer 1

I had a similar issue, but I was providing the string to the script as a local variable through a scope.
The local variable was a .NET CLR string, which is what caused the issue (please see here).

The solution for me was to convert the string passed to ERB.new to a Ruby string using to_s.

Here’s an example (Ruby snippet):

require 'erb'

template = ERB.new(template_code.to_s)
template.result(binding)

The C# Part which invoked the above script:

var scriptEngine = Ruby.CreateEngine();
var templateCode = "my ERB template code goes here";
// Pass the template code to the Ruby script through a scope
var scope = _scriptEngine.CreateScope(new Dictionary<string, object>() 
                                                  { 
                                                    {"template_code", templateCode}
                                                  });

var result scriptEngine.Execute(_boostrapScript, scope).ToString();

In the above C# snippet, _bootstrapScript is a string which contains the Ruby snippet above.