Lambda and delegate types

[GeroL]

Hi,

how do I write lambda function as Expressions?
I have this code:

Expression<Func<double, bool>> exprCast = (param) => System.Convert.ToBoolean(param);

It gives me this error:
Cannot convert anonymous method block to type 'type' because it is not a delegate type

[dadhi]

I don't see the problem https://dotnetfiddle.net/eSKXs0

[GeroL]

Yes it works with System.Linq.Expressions but not with FEC

[dadhi]

FEC is orthogonal to the hoisted lambda, because it is a C# compiler feature. Could you provide the full test to see what's failing?