C# 10 - string interpolation

DefaultInterpolatedStringHandler_sample.cs

// Refer to tweet - https://twitter.com/Dave_DotNet/status/1682699744747958274
// This code allocates same 72 bytes in GC Heap.

// However this may be slower than string.Create, because DefaultInterpolatedStringHandler is made for more general purpose.

// C# 10+ and .NET 6+
string title = "Mr.";
string first = "David";
string middle = "Patrick";
string last = "Callan";

{
    string text = $"{title} {first} {middle} {last}"; // 72 bytes in GC Heap
}

// Upper code is translated as follows by Roslyn compiler

{
    DefaultInterpolatedStringHandler d = new DefaultInterpolatedStringHandler(3, 4);
    d.AppendFormatted(title);
    d.AppendLiteral(" ");
    d.AppendFormatted(first);
    d.AppendLiteral(" ");
    d.AppendFormatted(middle);
    d.AppendLiteral(" ");
    d.AppendFormatted(last);

    string text = d.ToStringAndClear();
}