This document discusses new features in C# 7 and 8, including pattern matching, tuples, out variables, discards, ref returns and locals, expression-bodied members, numeric literals, local functions, generalized async returns, default literals, non-trailing named arguments, leading separators for numeric literals, private protected access, reference semantics with value types using in, ref, and ref readonly. It also provides links to documentation and proposals for each feature.
These are the slides from my C++Now 2018 talk. You can find the recording here: https://www.youtube.com/watch?v=y7PBciQp0B8. All my other talks can be found here: https://train-it.eu/resources.
---
Presentation of features already voted into C++20 Standard Draft in Toronto, Albuquerque, and Jacksonville ISO C++ Committee Meetings as well as the overview of other really promising proposals that have high chances to arrive in C++20.
These are the slides from my C++Now 2018 talk. You can find the recording here: https://www.youtube.com/watch?v=y7PBciQp0B8. All my other talks can be found here: https://train-it.eu/resources.
---
Presentation of features already voted into C++20 Standard Draft in Toronto, Albuquerque, and Jacksonville ISO C++ Committee Meetings as well as the overview of other really promising proposals that have high chances to arrive in C++20.
Slides for the Cluj.py meetup where we explored the inner workings of CPython, the reference implementation of Python. Includes examples of writing a C extension to Python, and introduces Cython - ultimately the sanest way of writing C extensions.
Also check out the code samples on GitHub: https://github.com/trustyou/meetups/tree/master/python-c
Description
At Stitch Fix most application logs are output in a structured JSON format for simpler debugging and downstream consumption.
In this talk we’ll cover in more detail why structured logs are useful and provide leverage, caveats to using them, and how simple it is to get one going with Python.
Abstract
At Stitch Fix most application logs are output in a structured JSON format for simpler debugging and downstream consumption. For example, data scientists can add a field to their application log and it will automatically turn up as a parsed field in Elasticsearch for easy dashboarding and querying via Kibana, or be easily found and queried in Presto. In this talk we’ll cover in more detail why structured logs are useful and provide leverage, caveats to using them, and how simple it is to get one going with Python.
simple pattern printing programme in c language for beginners.
here you can see code with its pattern programme and easily can understand the programme.
Slides for the Cluj.py meetup where we explored the inner workings of CPython, the reference implementation of Python. Includes examples of writing a C extension to Python, and introduces Cython - ultimately the sanest way of writing C extensions.
Also check out the code samples on GitHub: https://github.com/trustyou/meetups/tree/master/python-c
Description
At Stitch Fix most application logs are output in a structured JSON format for simpler debugging and downstream consumption.
In this talk we’ll cover in more detail why structured logs are useful and provide leverage, caveats to using them, and how simple it is to get one going with Python.
Abstract
At Stitch Fix most application logs are output in a structured JSON format for simpler debugging and downstream consumption. For example, data scientists can add a field to their application log and it will automatically turn up as a parsed field in Elasticsearch for easy dashboarding and querying via Kibana, or be easily found and queried in Presto. In this talk we’ll cover in more detail why structured logs are useful and provide leverage, caveats to using them, and how simple it is to get one going with Python.
simple pattern printing programme in c language for beginners.
here you can see code with its pattern programme and easily can understand the programme.
Design Patterns - Compiler Case Study - Hands-on ExamplesGanesh Samarthyam
This presentation takes a case-study based approach to design patterns. A purposefully simplified example of expression trees is used to explain how different design patterns can be used in practice. Examples are in C#, but is relevant for anyone who is from object oriented background.
Create the equivalent of a four function calculator. The program should request the user to enter a number, an operator, and another number. carry out the specified arithmetical operation: adding, subtracting, multiplying, or dividing the two numbers. (Using switch statement ).ThesisScientist.com
The PVS-Studio team is now actively developing a static analyzer for C# code. The first version is expected by the end of 2015. And for now my task is to write a few articles to attract C# programmers' attention to our tool in advance. I've got an updated installer today, so we can now install PVS-Studio with C#-support enabled and even analyze some source code. Without further hesitation, I decided to scan whichever program I had at hand. This happened to be the Umbraco project. Of course we can't expect too much of the current version of the analyzer, but its functionality has been enough to allow me to write this small article.
"Optimization of a .NET application- is it simple ! / ?", Yevhen TatarynovFwdays
Optimization of .NET application seems complex and tied full task, but don’t hurry up with conclusions. Let’s look on several cases from real projects.
For this we:
look under the hood of an application from a real project;
define the metric for optimization;
choose the necessary tools;
find bottlenecks /memory leaks and best practice to resolve them.
We'll improve the application step by step and we’ll what with simple analysis and simple best practice we can significantly reduce total resources usage.
The Present and The Future of Functional Programming in C++Alexander Granin
Keynote talk for C++ Siberia 2019.
I'm speaking about why Functional Programming is important in C++ world, what is the philosophy of FP in C++, and what features do we have. I'm presenting a connection of constexpr and template metaprogramming to pure FP, and talking about why monads are inevitable. I'm also discussing an upcoming features in C++.
C++ is a middle-level programming language developed by Bjarne Stroustrup starting in 1979 at Bell Labs. C++ runs on a variety of platforms, such as Windows, Mac OS, and the various versions of UNIX.
This reference will take you through simple and practical approach while learning C++ Programming language.
Community-driven Language Design at TC39 on the JavaScript Pipeline Operator ...Igalia
By Daniel Ehrenberg.
Slides at https://docs.google.com/presentation/d/1bpvESaWtNnhXV0a95b6GWHhhqUVnGCIPcs37ngqx4Uo/edit#slide=id.g38b91fc952_0_103
Following ES6, TC39 is working with the broader JS developer community to continue evolving the JavaScript programming language. The pipeline operator `x |> f |> g` is an early stage, community-driven proposal to make it easier to compose multiple functions, inspired by similar syntax in other programming language and frameworks like RxJS. In this talk, I'll explain how TC39 works and how this proposal is being carefully developed with extensive feedback and opportunities for you to get involved.
(c) WorkerConf 2018
28th June 2018 (Dornbirn, Austria)
https://worker.sh/
Similar to TDC2018SP | Trilha .Net - Novidades do C# 7 e 8 (20)
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
6. Acreditamos que a diversidade, em
suas diversas expressões, deve ser
respeitada e valorizada, e que uma
sociedade mais diversa é uma
sociedade melhor.
diversidade.tech
21. public static int DiceSum(IEnumerable<object> values)
{
var sum = 0;
foreach (var item in values)
{
if (item is int val)
sum += val;
else if (item is IEnumerable<object> subList)
sum += DiceSum(subList);
}
return sum;
}
https://docs.microsoft.com/dotnet/csharp/pattern-matching
http://bit.ly/cspatternmatching
23. case 0:
break;
case int val:
sum += val;
break;
case PercentileDie die:
sum += die.Multiplier * die.Value;
break;
https://docs.microsoft.com/dotnet/csharp/pattern-matching
public static int DiceSum(IEnumerable<object> values)
{
var sum = 0;
foreach (var item in values)
{
switch (item)
{
}
}
return sum;
}
http://bit.ly/cspatternmatching
24. case 0:
break;
case int val:
sum += val;
break;
case PercentileDie die:
sum += die.Multiplier * die.Value;
break;
https://docs.microsoft.com/dotnet/csharp/pattern-matching
case IEnumerable<object> subList when subList.Any():
sum += DiceSum(subList);
break;
case IEnumerable<object> subList:
break;
case null:
break;
default:
throw new InvalidOperationException("unknown");
public static int DiceSum(IEnumerable<object> values)
{
var sum = 0;
foreach (var item in values)
{
switch (item)
{
}
}
return sum;
}
http://bit.ly/cspatternmatching
26. void M()
{
var (name, company) = Person.Get();
WriteLine($"{name}, {company}");
}
class Person
{
public string Name { get; set; }
public string Company { get; set; }
public void Deconstruct(out string name, out string company)
{
name = Name;
company = Company;
}
public static Person Get() => new Person { Name = "…", Company = "…" };
} https://docs.microsoft.com/dotnet/csharp/tupleshttp://bit.ly/cstuplas
27. var numbers = (one: 1, two: 2);
var (uno, due) = numbers;
WriteLine($"{uno}, {due}");
https://docs.microsoft.com/dotnet/csharp/tuples
http://bit.ly/cstuplas
28. if (int.TryParse("1", out int result))
WriteLine(result);
if (int.TryParse("1", out var result2))
WriteLine(result2);
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#out-variables
http://bit.ly/csoutvars
29. (int x, int y) GetCoordinates() => (1, 2);
var (_, y) = GetCoordinates();
https://docs.microsoft.com/dotnet/csharp/discards
http://bit.ly/csdiscards
31. if (int.TryParse("1", out _))
WriteLine("It is a number!");
https://docs.microsoft.com/dotnet/csharp/discards
http://bit.ly/csdiscards
32. object o = 1;
if (o is Person p)
WriteLine(p.Company);
else if (o is null)
WriteLine("null");
else if (o is var _)
WriteLine("Unknown");
https://docs.microsoft.com/dotnet/csharp/discards
http://bit.ly/csdiscards
33. ref int Find(int[,] matrix, Func<int, bool> predicate)
{
for (int i = 0; i < matrix.GetLength(0); i++)
for (int j = 0; j < matrix.GetLength(1); j++)
if (predicate(matrix[i, j]))
return ref matrix[i, j];
throw new InvalidOperationException("Not found");
}
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#ref-locals-and-returns
http://bit.ly/csreflocals
34. void M()
{
var matrix = new [,] { { 1, 2, 3, 4, 5 },
{ 6, 7, 8, 42, 10 } };
ref var item = ref Find(matrix, val => val == 42);
WriteLine(item);
item = 24;
WriteLine(matrix[1, 3]);
}
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#ref-locals-and-returns
http://bit.ly/csreflocals
35. public ExpressionBodiedMembers(string name) => Name = name;
~ExpressionBodiedMembers() => WriteLine("Finalized!");
private string name;
public string Name
{
get => name;
set => name = value;
}
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#more-expression-bodied-members
http://bit.ly/csmaisebm
36. private string a = GetA() ?? throw new Exception();
private static string GetA() => throw new Exception();
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#throw-expressions
http://bit.ly/csexpthrow
37. int sixteen = 0b0001_0000;
int thirtyTwo = 0b0010_0000;
int sixtyFour = 0b0100_0000;
int oneHundredTwentyEight = 0b1000_0000;
long oneHundredBillions = 100_000_000_000;
double AvogadroConstant = 6.022_140_857_747_474e23;
decimal GoldenRatio = 1.618_033_988_749M;
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#numeric-literal-syntax-improvements
http://bit.ly/csnumlit
38. double Average(IEnumerable<int> ns)
{
double Divide(double a, double b)
{
if (b == 0) throw new DivideByZeroException();
return a / b;
}
var sum = ns.Sum();
return Divide(sum, ns.Count());
}
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#local-functions
http://bit.ly/cslocalfunc
39. void Add1AndSumAll(int[] ms)
{
IEnumerable<int> Sum1(IEnumerable<int> ns)
{
foreach (var n in ns)
yield return n + 1;
}
if (ms == null) throw new NullReferenceException();
WriteLine(Sum1(ms).Sum());
}
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#local-functions
http://bit.ly/cslocalfunc
41. public async ValueTask<int> SumAsync(IEnumerable<ValueTask<int>> ns)
{
var sum = 0;
foreach (var nTask in ns)
{
var n = await nTask;
sum += n;
}
return sum;
}
https://docs.microsoft.com/dotnet/csharp/whats-new/csharp-7#generalized-async-return-types
http://bit.ly/csasyncgeneral
48. void M(int i, int j) { }
void N()
{
M(i: 2, 3);
}
https://github.com/dotnet/csharplang/blob/master/proposals/csharp-7.2/non-trailing-named-arguments.md
http://bit.ly/csntna
49. var m = 0b_101; //5
var n = 0x_00C0; // 192
https://github.com/dotnet/csharplang/blob/master/proposals/csharp-7.2/leading-separator.md
http://bit.ly/cs_num
50. class Base
{
private protected int f;
}
class DerivedInSameAssembly : Base
{
void M()
{
var x = base.f;
}
}
class DerivedInOtherAssembly : Base
{
void M()
{
var x = base.f; //error
}
}
https://github.com/dotnet/csharplang/blob/master/proposals/csharp-7.2/private-protected.md
http://bit.ly/csprpr
51. Vector Add(in Vector v1, in Vector v2)
{
v1 = default(Vector); // not OK!!
v1.X = 0; // not OK!!
Foo(ref v1.X); // not OK!!
// OK:
return new Vector(v1.X +v2.X, v1.Y + v2.Y);
}
https://docs.microsoft.com/dotnet/csharp/reference-semantics-with-value-types
http://bit.ly/csmodin
53. public static Ponto Subtrai(ref this Ponto p1, ref Ponto p2) =>
new Ponto(p1.X - p2.X, p1.Y - p2.Y);
void Ref()
{
Ponto p1 = new Ponto(1, 2), p2 = new Ponto(3, 4);
var pResultado = p1.Subtrai(ref p2);
p1.Subtrai(ref new Ponto()); // não compila
new Ponto().Subtrai(ref p1); // não compila
}
https://github.com/dotnet/csharplang/blob/master/proposals/csharp-7.2/readonly-ref.md#refin-extension-methods
http://bit.ly/csextref
55. ref readonly Vector FetchOrigin() => ref origin;
void M()
{
var v1 = new Vector(1, 2, 3);
var v2 = new Vector(4, 5, 6);
var vSum = Add(v1, v2);
ref readonly var origin = ref FetchOrigin();
}
private readonly Vector origin = new Vector(0, 0, 0);
https://docs.microsoft.com/dotnet/csharp/reference-semantics-with-value-types
http://bit.ly/csretrefro
56. ref readonly var origin = ref FetchOrigin();
var origin2 = FetchOrigin(); // copy created
https://docs.microsoft.com/dotnet/csharp/reference-semantics-with-value-types
http://bit.ly/csretrefro
57. readonly struct Ponto
{
public Ponto(float x, float y)
{
X = x;
Y = y;
}
public float X { get; }
public float Y { get; }
private readonly static Ponto origem = new Ponto();
public static ref readonly Ponto Origem => ref origem;
}
https://docs.microsoft.com/dotnet/csharp/reference-semantics-with-value-types#readonly-struct-type
http://bit.ly/csrostruct
58. ref readonly var p = ref Ponto.Origem;
var x = p.X; // sem cópia
https://docs.microsoft.com/dotnet/csharp/reference-semantics-with-value-types#readonly-struct-type
http://bit.ly/csrostruct
60. ref struct TwoSpans<T>
{
// pode ter campos desde que não sejam classes
public Span<T> first;
public Span<T> second;
}
// erro: arrays of ref-like types are not allowed.
TwoSpans<int>[] arr = null;
https://docs.microsoft.com/en-us/dotnet/csharp/reference-semantics-with-value-types#ref-struct-type
61. readonly ref struct ReadOnlyRefPoint2D
{
public int X { get; }
public int Y { get; }
public ReadOnlyRefPoint2D(int x, int y) =>
(X, Y) = (x, y);
}
https://docs.microsoft.com/dotnet/csharp/reference-semantics-with-value-types#readonly-ref-struct-type
62. void M()
{
Span<int> arr = stackalloc int[3];
}
https://msdn.microsoft.com/en-us/magazine/mt814808.aspx
Não é unsafe
64. Span<int> RowFive = new Span<int>(PascalsTriangle, 10, 5);
fixed (int* ptrToRow = RowFive)
{
// Soma os números 1,4,6,4,1
var sum = 0;
for (int i = 0; i < RowFive.Length; i++)
{
sum += *(ptrToRow + i);
}
Console.WriteLine(sum);
}
https://github.com/dotnet/csharplang/blob/master/proposals/csharp-7.3/pattern-based-fixed.md
int[] PascalsTriangle = {
1,
1, 1,
1, 2, 1,
1, 3, 3, 1,
1, 4, 6, 4, 1,
1, 5, 10, 10, 5, 1 };
Span<T>.GetPinnableReference()
65. unsafe struct S
{
public fixed int myFixedField[10];
}
class C
{
private static S s = new S();
unsafe public void M()
{
int p = s.myFixedField[5];
}
}
https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-7-3#indexing-fixed-fields-does-not-require-pinning
// CSharp 7.2
fixed (int* ptr = s.myFixedField)
{
int p = ptr[5];
}
66. var structs = new StructGrande[]
{ new StructGrande(), new StructGrande() };
ref StructGrande refLocal = ref structs[0];
refLocal = ref structs[1];
https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-7-3#ref-local-variables-may-be-reassigned
68. unsafe public static byte[] ToByteArray<T>
(this T argument) where T : unmanaged
{
var size = sizeof(T);
var result = new byte[size];
byte* p = (byte*)&argument;
for (var i = 0; i < size; i++)
result[i] = *p++;
return result;
}
https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/generics/constraints-on-type-parameters#unmanaged-constraint
69. public static TDelegate TypeSafeCombine<TDelegate>
(this TDelegate source, TDelegate target)
where TDelegate : System.Delegate =>
System.Delegate.Combine(source, target)
as TDelegate;
Action first = () => Console.WriteLine("this");
Action second = () => Console.WriteLine("that");
var combined = first.TypeSafeCombine(second);
combined();
https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/generics/constraints-on-type-parameters#delegate-constraints
70. public static Dictionary<int, string> EnumNamedValues<T>()
where T : System.Enum
{
var result = new Dictionary<int, string>();
var values = Enum.GetValues(typeof(T));
foreach (int item in values)
result.Add(item, Enum.GetName(typeof(T), item));
return result;
}
enum Rainbow { Red, Orange, Yellow, Green, Blue, Indigo, Violet }
var map = EnumNamedValues<Rainbow>();
foreach (var pair in map)
Console.WriteLine($"{pair.Key}:t{pair.Value}");
https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/generics/constraints-on-type-parameters#enum-constraints
73. public class Foo
{
protected Foo(out int i) => i = 1;
}
public class Bar : Foo
{
public int Value { get; }
public Bar() : base(out int value) => Value = value;
}
https://github.com/dotnet/csharplang/blob/master/proposals/csharp-7.3/expression-variables-in-initializers.md
74. public class Baz
{
private readonly int field1 =
int.TryParse(SomeStatic.Text, out int value)
? Value
: -1;
}
https://github.com/dotnet/csharplang/blob/master/proposals/csharp-7.3/expression-variables-in-initializers.md
77. public class Cartesian { public int X { get; } public int Y { get; } }
public class Polar
{
public static bool operator is(Cartesian c, out double R, out double Theta)
{
R = Math.Sqrt(c.X * c.X + c.Y * c.Y);
Theta = Math.Atan2(c.Y, c.X);
return c.X != 0 || c.Y != 0;
}
}
void M()
{
var c = new Cartesian(3, 4);
if (c is Polar(var R, _)) WriteLine(R);
}
https://github.com/dotnet/csharplang/blob/master/proposals/patterns.md
78. void N(string? aNullableString, bool condition) {
WriteLine(aNullableString.Length); // warning
if (aNullableString != null)
WriteLine(aNullableString); // no warning
if (!string.IsNullOrWhiteSpace(aNullableString))
WriteLine(aNullableString!.Length); // I know better
var anotherNullableString = condition ? "Hello" : aNullableString;
WriteLine(anotherNullableString.Length); // warning
var yetAnotherNullableString = condition ? "Hello" : null;
WriteLine(yetAnotherNullableString.Length); // warning
string nonNullableString = null; //warning
WriteLine(nonNullableString); // no warning
}
https://github.com/dotnet/csharplang/blob/master/proposals/nullable-reference-types.md
https://github.com/dotnet/roslyn/blob/features/NullableReferenceTypes/docs/features/NullableReferenceTypes/README.md
79. async Task M()
{
foreach await (var i in GetStream())
WriteLine(i);
}
IAsyncEnumerable<int> GetStream() => new[] { 1, 2, 3 }.ToAsyncEnumerable();
async IAsyncEnumerable<int> MyIterator()
{
for (int i = 0; i < 100; i++)
{
await Task.Delay(1000);
yield return i;
}
}
https://github.com/dotnet/csharplang/blob/master/proposals/async-streams.md
80. using await (IAsyncDisposable resource = await store.GetRecordAsync(…)) { … }
class Foo : IAsyncDisposable
{
public async Task DisposeAsync()
{
await ...
}
}
https://github.com/dotnet/csharplang/blob/master/proposals/async-streams.md
81. interface I
{
void M() { WriteLine("I.M"); }
}
class C : I { } // OK
void M()
{ I i = new C();
i.M(); // prints "I.M"
}
https://github.com/dotnet/csharplang/blob/master/proposals/default-interface-methods.md
83. // list[Index.CreateFromEnd(1)]
var ultimoItem = list[^1];
// list[Index.CreateFromEnd(2)]
var penultimoItem = list[^2];
// list[3, Index.CreateFromEnd(2)]
var multiDimensional = list[3, ^2];
https://github.com/dotnet/csharplang/blob/master/proposals/ranges.md
84. // list[Range.Create(2, Index.CreateFromEnd(3))]
var slice1 = list[2..^3];
// list[Range.ToEnd(Index.CreateFromEnd(3))]
var slice2 = list[..^3];
// list[Range.FromStart(2)]
var slice3 = list[2..];
// list[Range.All]
var slice4 = list[..];
// list[Range.Create(1, 2), Range.All]
var multiDimensional = list[1..2, ..]
https://github.com/dotnet/csharplang/blob/master/proposals/ranges.md
85. class Person : IEquatable<Person>
{
public string First { get; }
public string Last { get; }
public Person(string First, string Last) => (this.First, this.Last) = (First, Last);
public void Deconstruct(out string First, out string Last)
=> (First, Last) = (this.First, this.Last);
public bool Equals(Person other)
=> other != null && First == other.First && Last == other.Last;
public override bool Equals(object obj) => obj is Person other ? Equals(other) : false;
public override int GetHashCode() => GreatHashFunction(First, Last);
…
}
class Person(string First, string Last);
https://github.com/dotnet/csharplang/blob/master/proposals/records.md
86. extension class Enrollee extends Person
{
// static field
static Dictionary<Person, Professor> enrollees = new Dictionary<Person, Professor>();
// instance method
public void Enroll(Professor supervisor) { enrollees[this] = supervisor; }
// instance property
public Professor Supervisor => enrollees.TryGetValue(this, out var supervisor) ? supervisor : null;
// static property
public static ICollection<Person> Students => enrollees.Keys;
// instance constructor
public Person(string name, Professor supervisor) : this(name) { this.Enroll(supervisor); }
}
https://github.com/dotnet/csharplang/issues/192
87. public shape SGroup<T>
{
static T operator +(T t1, T t2);
static T Zero { get; }
}
https://github.com/dotnet/csharplang/issues/164
88. public static AddAll<T>(T[] ts) where T : SGroup<T>
{
var result = T.Zero;
foreach (var t in ts) { result += t; }
return result;
}
https://github.com/dotnet/csharplang/issues/164
89. public shape SGroup<T>
{
static T operator +(T t1, T t2);
static T Zero { get; }
}
https://github.com/dotnet/csharplang/issues/164
90.
91. w w w. l a m b d a 3 . c o m . b r
Obrigado!
Giovanni Bassi
@giovannibassi
/giggio.tech