cs7.0-PrintCoordinates-discard.cs

p.GetCoordinates(out var x, out _); // I only care about x

I'm under the impression that _ is a valid variable name by itself, which would make this code ambiguous:

int _;                                  // Funny name, but valid. Variable is uninitialized.
p.GetCoordinates(out var x, out _);     // Variable x is declared here.  Is the second param ignored? or is variable `_` used as an out-param?
WriteLine($"Got Coords {x} and {_}");   // Ambiguous: is _ still uninitialized? or was the value set by previous line?

See : https://msdn.microsoft.com/en-us/library/gg615485%28v=vs.88%29.aspx#Variables The section on "Variable Naming"

I also had the same thought, @abelenky.

If _ was declared. It works like pre C# 7.0.

The _ is a discard in C# 7.0