ufcpp

unsafe
{
    Circle circle = new() { Radius = 1 };
    Rectangle rectangle = new() { Width = 2, Height = 3 };
    Rectangle square = new() { Width = 2, Height = 2 };

    Console.WriteLine(Algorithm.AreaRatio(0, &circle));
    Console.WriteLine(Algorithm.AreaRatio(1, &rectangle));
    Console.WriteLine(Algorithm.AreaRatio(1, &square));

ufcpp

for (uint i = 0; i < 12; i++)
{
    Console.WriteLine(format(i));
}

for (uint i = 15; i < 120; i+=7)
{
    Console.WriteLine(format(i));
}
Console.WriteLine(format(1234));

ufcpp

using System.Collections;
using System.Runtime.CompilerServices;

var d = new Dictionary<int, string> { { 1, "one" }, { 2, "two" } };
ICovariantDictionary<int, string> cd = d.AsCovariant();

// TValue が out なので string → object 代入可能。
ICovariantDictionary<int, object> id = cd;

foreach (var (k, v) in id)

ufcpp

namespace TimeProviderExtension;

public class PausableTimeProvider(TimeProvider innerProvider) : TimeProvider
{
    public PausableTimeProvider() : this(System) { }

    private long _pausedTimestamp = innerProvider.GetTimestamp();
    private long _offsetTimestamp = 0;
    private DateTimeOffset _pausedUtcNow = innerProvider.GetUtcNow();
    private TimeSpan _offsetUtcNow = default;

ufcpp

using System.Runtime.CompilerServices;

var p = new Private();
Console.WriteLine(p.Value); // 0

Accessor r = p; // implicit cast で p の参照が r に渡る。
r.Value = 1;
Console.WriteLine(p.Value); // 書き変わってる。

// PrivateProxy 触りつつ、

ufcpp

class A(int x)
{
    int _x = x; // これはキャプチャしない。
}

class B(int x)
{
    public int X { get; } = x; // これもキャプチャしない。
}

ufcpp

X.M(0); // 整数リテラルの自然な型は int
X.M(default); // でも、 default は「サイズが小さい型優先」っぽい

// そういう仕様？意図的？

class X
{
    public static void M(int i32) { }
    public static void M(short i16) { }
}

ufcpp

using System.Globalization;
using System.Text.RegularExpressions;
using static System.Console;

var s1 = "a\u0301"; // á = a + ́
var s2 = "\u00e1"; // á

// たとえ InvariantCulture でも。
// <InvariantGlobalization>false</InvariantGlobalization> な限り。
// (↑true のときは、StringComparison.Default が Ordinal になる効果もあり。)

ufcpp

using System.Buffers.Text;
using System.Diagnostics.CodeAnalysis;
using System.Runtime.InteropServices;

var x = 0x12345678;
Console.WriteLine($"{x.Hex()}");

public static class Format
{
    public static AsciiBuffer8 Hex(this int x)

ufcpp

using System.Buffers.Binary;

var x = 0x12345678;

Console.WriteLine($"{x:X}");
Console.WriteLine($"{x.Little()}");

static class LittleEndianExtensions
{
    public static LittleEndianInt32 Little(this int x) => new(x);