I'm not sure this is the correct place for this, but the GitHub page led me to this place.
I believe I have found a problem in the 1.5.1 ClojureCLR currently on GitHub. The problem is with the initialization of the static Compiler class.
According to section 10.4.5.1 of the MSDN documentation, the fields of a static class are evaluated "in textual order".
Unfortunately, this line:
public static readonly Symbol FnOnceSym = (Symbol) Symbol.intern("fn*").withMeta(RT.map(Keyword.intern(null, "once"), true));
comes before this line:
static Dictionary<String, Type> _duplicateTypeMap = new Dictionary<string, Type>();
The evaluation of the first causes a call to the static method FindDuplicateType() within the same class, and this method uses the _duplicateTypeMap without a null check. This causes a null exception to be thrown because the initializer for _duplicateTypeMap hasn't executed yet.
My solution is to add a section at the very top of the Compiler class for "dependency" intializations - consisiting only of the initialization of _duplicateTypeMap at this point, to give a home to all such initializations that get used by the other static initializers.
There is no "Issues" section on the GitHub page, or I would have logged an issue there. Please let me know the best way to get this issue evaluated for a future release of the compiler.
Brian C. Barnes