What is the operator precedence of C# null-coalescing (??) operator?

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Aside from what you’d like the precedence to be, what it is according to ECMA, what it is according to the MS spec and what csc actually does, I have one bit of advice:

Don’t do this.

I think it’s much clearer to write:

string c = (a ?? "") + (b ?? "");

Alternatively, given that null in string concatenation ends up just being an empty string anyway, just write:

string c = a + b;

EDIT: Regarding the documented precedence, in both the C# 3.0 spec (Word document) and ECMA-334, addition binds tighter than ??, which binds tighter than assignment. The MSDN link given in another answer is just wrong and bizarre, IMO. There’s a change shown on the page made in July 2008 which moved the conditional operator – but apparently incorrectly!

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