Even more stuff

[Laoujin]

using, IDisposableAsync, blocks

void Multiply<T>(T a, T b) where T : INumber<T>
{
    var result = a * b;
}

pattern matching:
is (not) null

[Laoujin]

public record Test(IEnumerable<string> Moons) { }

[Fact]
public void Testy()
{
    var t1 = new Test(new[] { "Aie" });
    var t2 = new Test(new[] { "Aie" });
    var result = t1.Equals(t2);
    Assert.True(result); // Fails
}

[Fact]
public void Testy2()
{
    var col = new[] { "Aie" };
    var t1 = new Test(col);
    var t2 = new Test(col);
    var result = t1.Equals(t2);
    Assert.True(result); // Succeeds
}

[Laoujin]

Linq: CountBy, AggregateBy

• Small refresher on Deferred execution?
• Multiple looping over IEnumerable?
• IEnumerable vs IQueryable?