controlflow

using System;
using JetBrains.Annotations;

namespace Smth {
  [PublicAPI]
  public abstract class ReflectionTypeVisitor<T> {
    public virtual T VisitSimpleType(Type type) => default(T);
    public virtual T VisitConstructedType([NotNull] Type typeDefinition, [NotNull] Type[] typeArguments) => default(T);
    public virtual T VisitTypeParameterType([NotNull] Type typeParameter) => default(T);
    public virtual T VisitArrayType([NotNull] Type arrayType) => default(T);

controlflow

using System;
using System.Collections.Generic;
using System.ComponentModel;
using JetBrains.Annotations;

namespace JetBrains.VsIntegration.ProjectModel.PropertiesExtender
{
  public sealed class AggregatedPropertyDescriptor : PropertyDescriptor
  {
    [NotNull] private readonly IList<PropertyDescriptor> myPropertyDescriptors;

controlflow

class Foo {
  [ProvidesContext] IPredefinedType _predefinedTypes = ...;
  
  void DoSomething(ITreeNode node) {
    if (Check(node)) {
      var expressionType = node.GetExpressionType();
      if (expressionType.Equals(node.GetPredefinedType().Bool) {
                             // ^^^^^^^^^^^^^^^^^^^^^^^^
                             // Use aleady provided 'IPredefinedType' value from '_predefinedTypes' field 
      }

controlflow

// 1
smth?.Foo()     smth.Foo()
    ?.Foo()         .Foo()
    .Foo()          ?.Foo()
    ?.Foo()         .Foo()
    .Foo()          ?.Foo()
    .Foo();         ?.Foo();

// 2
smth?.Foo()      smth.Foo()

controlflow

var x = e as T;
if (x != null) {
  ...
} else {
  // no usages of 'x' here
}
// no usages of 'x' here too

// =>

controlflow

T t;
U u;
if ((t = x.P as T) != null &&
    (u = t.P as U) != null) {
  // ... use u/t ...
}

// =>

if (x.P is T t &&

controlflow

    public static bool IsInContantContext([NotNull] this ITreeNode context)
    {
      foreach (var containingNode in context.ContainingNodes())
      {
        switch (containingNode)
        {
          case IAttribute attribute:
          case IConstantDeclaration constant:
          case ILocalConstantDeclaration localConstant:
          case IEnumMemberDeclaration enumMember:

controlflow

using System;
using System.Collections.Generic;

public static class C {
    public static void M() {
        var xs = new Dictionary<int, string>();
        foreach ((int id, string key) in xs) {
            // ...
            // int a = 0, b = 1;
            // ...

controlflow

        var typeArgumentListScanKind = ScanTypeArgumentList(nameOptions);
        if (typeArgumentListScanKind == ScanTypeArgumentListKind.DefiniteTypeArgumentList) return true;

        if (typeArgumentListScanKind == ScanTypeArgumentListKind.PossibleTypeArgumentList)
        {
          if ((nameOptions & NameOptions.InTypeList) != 0)
          {
            return true;
          }
        }

controlflow

while (myLexer.TokenType == CSharpTokenType.DOT ||
       myLexer.TokenType == CSharpTokenType.DOUBLE_COLON)
{
  // ...
}

// =>

while (myLexer.TokenType is var tt && (tt == CSharpTokenType.DOT ||
                                       tt == CSharpTokenType.DOUBLE_COLON))