Visual Studio Single File Generator to run roslyn Syntax Walker and generate additional members

I've created a custom tool for Visual Studio that runs your custom roslyn Syntax Walker to generate additional members. This is my way for emulating the lack of metaprogramming using roslyn in C#.

https://github.com/xiety/RoslynGenerator

For example, I've used it for generating Identity Value Types:

In AccountId.cs file:

[MetaIdentity("account")]
public partial struct AccountId : IIdentity
{
}

Assign RoslynGenerator as Custom Tool for this file, and it will generate AccountId.gen.cs file for you with some boilerplate code:


public partial struct AccountId
{
        private const string Prefix = "account-";
        private readonly string _value;

        public AccountId(string value){ _value = value; }

        public AccountId(long value)
                : this(Prefix + value){}

        public override bool Equals(object obj)
        {
            if (obj == null || obj.GetType() != typeof(AccountId)) return false;
            return _value == ((AccountId)obj)._value;
        }

        public override string ToString() => _value;
        public static implicit operator AccountId(string value) => new AccountId(value);
        public static implicit operator string (AccountId id) => id._value;
        public static bool operator ==(AccountId a, AccountId b) => a._value == b._value;
        public static bool operator !=(AccountId a, AccountId b) => !(a == b);
        public override int GetHashCode() => _value.GetHashCode();
}

To make this transformation RoslynGenerator finds in your project references class called MetaSyntaxWalker and runs it's Generate method dynamically passing SemanticModel and SyntaxRoot of current file.