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using System.Text.Json.Serialization;
using AotWebApi;
using Microsoft.Extensions.Options;

var builder = WebApplication.CreateSlimBuilder(args);

builder.Services.ConfigureHttpJsonOptions(options =>
{
    options.SerializerOptions.TypeInfoResolverChain.Insert(0, AppJsonSerializerContext.Default);
});

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namespace Microsoft.Extensions.Configuration.Binder.SourceGeneration
{
  [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = false)]
  // Specifies options to honor when generating binding logic.
  // Presence indicates that the source generator should be invoked for the current assembly.
  public sealed class BindingSourceGenerationOptionsAttribute : Attribute
  {
    // Specifies the generation mode.
    public BindingSourceGenerationMode GenerationMode { get; set; }
  }

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ConfigurationBinder source generator

Phase 1: Implement core binding functionality

Similar to fast-path JSON deserialization.

Current status Feature branch:

• core infra & generation implemented
• based on David's prototype which generates to global namespace, making compiler choose source-gen'd methods over framework methods
• testing mechanism same as JSON (sharing tests with reflection-based implementation)

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Layomi 📹

concentric circles in no order ㋛

• Visual art / versioned thoughts - VSCO
• Music I make & listen to - SoundCloud / Spotify
• .NET ~ libraries I help build 💻(that run on phones, the web, and spaceships) - GitHub / Twitter

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The default behavior of the System.Text.Json JsonSerializer and Utf8JsonWriter follows the behavior of JavascriptEncoder.Default, which means the following character sets are escaped:

• Any non-ascii character
• Characters required escaping based on the JSON RFC
• HTML-specific ascii characters

Current Approach

The current approach involves going through the list of characters, one at a time, and check whether that character needs escaping. We special case the "null" encoder (which is the default when the user doesn't specify their own) and use a 256 byte bit-mask to indicate which character needs to be escaped. https://github.com/dotnet/corefx/blob/52d63157c78c31816b81be1599a5dacf96b5e5ca/src/System.Text.Json/src/System/Text/Json/Writer/JsonWriterHelper.Escaping.cs#L82-L109

New Approach Chosen

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using System;
using System.Collections.Generic;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace RefHandlingDemo
{
    class Program
    {
        static void Main(string[] args)

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Approach A

/// <summary>
/// Prevents a property from being serialized or deserialized.
/// </summary>
[AttributeUsage(AttributeTargets.Property, AllowMultiple = false)]
public sealed class JsonIgnoreAttribute : JsonAttribute
{
    /// <summary>

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sudo ./build.sh -subsetCategory coreclr -configuration Release
__DistroRid: linux-x64
__RuntimeId: linux-x64
Downloading 'https://dot.net/v1/dotnet-install.sh'
Trying to run 'curl https://dot.net/v1/dotnet-install.sh -sSL --retry 10 --create-dirs -o /home/layomia/repos/dotnet_runtime/.dotnet/dotnet-install.sh' for maximum of 5 attempts.
Ran 'curl https://dot.net/v1/dotnet-install.sh -sSL --retry 10 --create-dirs -o /home/layomia/repos/dotnet_runtime/.dotnet/dotnet-install.sh' successfully.
dotnet_install: Warning: Unable to locate zlib. Probable prerequisite missing; install zlib.
dotnet-install: Downloading link: https://dotnetcli.azureedge.net/dotnet/Sdk/5.0.100-preview.3.20168.11/dotnet-sdk-5.0.100-preview.3.20168.11-linux-x64.tar.gz
dotnet-install: Extracting zip from https://dotnetcli.azureedge.net/dotnet/Sdk/5.0.100-preview.3.20168.11/dotnet-sdk-5.0.100-preview.3.20168.11-linux-x64.tar.gz
dotnet-install: Adding to current process PATH: `/home/layomia/repos/dotnet_runtime/.dotnet`. Note: This change will

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Deserializing objects using parameterless constructors with JsonSerializer

Motivation

JsonSerializer deserializes instances of objects (classes and structs) using public parameterless constructors. If none is present, and deserialization is attempted, the serializer throws a NotSupportedException with a message stating that objects without public parameterless constructors, including interfaces and abstract types, are not supported for deserialization. There is no way to deserialize an instance of an object using a parameterized constructor.

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Deserialize LoginViewModel

Method	Mean	Error	StdDev	Median	Min	Max	Gen 0	Gen 1	Gen 2	Allocated
Jil	492.3 ns	11.13 ns	11.43 ns	488.6 ns	479.8 ns	522.1 ns	0.0629	-	-	264 B
JSON.NET	1,288.4 ns	26.17 ns	67.55 ns	1,263.9 ns	1,209.4 ns	1,493.6 ns	0.6618	-	-	2776 B
Utf8Json	360.5 ns	3.07 ns	2.56 ns	360.4 ns	355.4 ns	365.5 ns	0.0668	-	-	280 B
Default	517.7 ns	3.63 ns	3.03 ns	517.3 ns	512.5 ns	522.3 ns	0.0391	-	-	168 B
AOT_LoadConverters	471.8 ns	9.14 ns	11.22 ns	469.3 ns	452.2 ns	494.5 ns	0.0401	-	-	168 B
AOT_Raw	402.2 ns	10.17 ns	9.51 ns