source: trunk/HeuristicLab.ExtLibs/HeuristicLab.NRefactory/5.5.0/NRefactory.CSharp-5.5.0/Resolver/LambdaResolveResult.cs @ 17197

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using System;
using System.Collections.Generic;
using ICSharpCode.NRefactory.Semantics;
using ICSharpCode.NRefactory.TypeSystem;

namespace ICSharpCode.NRefactory.CSharp.Resolver
{
  /// <summary>
  /// Represents an anonymous method or lambda expression.
  /// Note: the lambda has no type.
  /// To retrieve the delegate type, look at the anonymous function conversion.
  /// </summary>
  public abstract class LambdaResolveResult : ResolveResult
  {
    protected LambdaResolveResult() : base(SpecialType.UnknownType)
    {
    }
    
    /// <summary>
    /// Gets whether there is a parameter list.
    /// This property always returns true for C# 3.0-lambdas, but may return false
    /// for C# 2.0 anonymous methods.
    /// </summary>
    public abstract bool HasParameterList { get; }
    
    /// <summary>
    /// Gets whether this lambda is using the C# 2.0 anonymous method syntax.
    /// </summary>
    public abstract bool IsAnonymousMethod { get; }
    
    /// <summary>
    /// Gets whether the lambda parameters are implicitly typed.
    /// </summary>
    /// <remarks>This property returns false for anonymous methods without parameter list.</remarks>
    public abstract bool IsImplicitlyTyped { get; }
    
    /// <summary>
    /// Gets whether the lambda is async.
    /// </summary>
    public abstract bool IsAsync { get; }
    
    /// <summary>
    /// Gets the return type inferred when the parameter types are inferred to be <paramref name="parameterTypes"/>
    /// </summary>
    /// <remarks>
    /// This method determines the return type inferred from the lambda body, which is used as part of C# type inference.
    /// Use the <see cref="ReturnType"/> property to retrieve the actual return type as determined by the target delegate type.
    /// </remarks>
    public abstract IType GetInferredReturnType(IType[] parameterTypes);
    
    /// <summary>
    /// Gets the list of parameters.
    /// </summary>
    public abstract IList<IParameter> Parameters { get; }
    
    /// <summary>
    /// Gets the return type of the lambda.
    /// 
    /// If the lambda is async, the return type includes <code>Task&lt;T&gt;</code>
    /// </summary>
    public abstract IType ReturnType { get; }
    
    /// <summary>
    /// Gets whether the lambda body is valid for the given parameter types and return type.
    /// </summary>
    /// <returns>
    /// Produces a conversion with <see cref="Conversion.IsAnonymousFunctionConversion"/>=<c>true</c> if the lambda is valid;
    /// otherwise returns <see cref="Conversion.None"/>.
    /// </returns>
    public abstract Conversion IsValid(IType[] parameterTypes, IType returnType, CSharpConversions conversions);
    
    /// <summary>
    /// Gets the resolve result for the lambda body.
    /// Returns a resolve result for 'void' for statement lambdas.
    /// </summary>
    public abstract ResolveResult Body { get; }
    
    public override IEnumerable<ResolveResult> GetChildResults()
    {
      return new [] { this.Body };
    }
  }
}