Re: 1. MutableString is convertible to String, so why would you need an object parameter?
Tomas -----Original Message----- From: users-boun...@lists.ironpython.com [mailto:users-boun...@lists.ironpython.com] On Behalf Of Doug Blank Sent: Monday, April 04, 2011 8:25 AM To: Discussion of IronPython Subject: [IronPython] Writing cross-language libraries that appear native I'm working on writing C# libraries which can be imported by a variety of .NET languages, DLR and otherwise, which appear native to the language importing them. For example, writing a C# function that can be used naturally in IronPython as if it were written in Python, IronRuby as if it were written in Ruby, and F# as if it were written in F#, etc. I've encountered some gotchas that I thought I'd share, and looking for any other points of advice in writing cross-language libraries. 1. IronRuby strings aren't really strings, so you need to pass them in as an object, and call .ToString(). public static string expects_string(object val) { return val.ToString(); } 2. F# 2.0 doesn't seem to automatically convert a type to the associated nullable type, so avoid nullable types as parameters. // AVOID: public static double? expects_nullable(double? var1=null) { return var1; } // BETTER: public static double? expects_nullable() { return null; } public static double expects_nullable(double var1) { return var1; } 3. IronPython and IronRuby lists and dictionaries implement IList and IDictionary, so no problem with those. public static IDictionary<object,object> make_dict(object val) { if (val as IDictionary<object,object> != null) { return ((IDictionary<object,object>)val); } else throw new System.ArgumentException("object is not a dictionary"); } public static IList<object> make_list(object val) { if (val as IList<object> != null) { return ((IList<object>)val); } else throw new System.ArgumentException("object is not a list"); } Any other suggestions? -Doug _______________________________________________ Users mailing list Users@lists.ironpython.com http://lists.ironpython.com/listinfo.cgi/users-ironpython.com _______________________________________________ Users mailing list Users@lists.ironpython.com http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
