T4 Template to implement the Builder Pattern

MyTestClass.tt

<#@ template debug="false" hostspecific="false" language="C#" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ output extension=".cs" #>
<# 
    var nsName = "Testing";
    var className = "MyTestClass";
    var accessor = "public";
    var classCtorAccessor = "public";

    // Property Name => Type
    var properties = new List<Tuple<string, string>>
    {
        Tuple.Create("RequestId", "string"),
        Tuple.Create("Foo", "int")
    };

    Func<string, string> PropToArg = (prop) => prop.Substring(0,1).ToLower() + prop.Substring(1);

    var ctorList = string.Join(", ", properties.Select(kvp => kvp.Item2 + " " + PropToArg(kvp.Item1)));
#>
namespace <#= nsName #>
{
    <#= accessor #> partial class <#= className #>
    {
        partial void ValidateArgument(string argName, object value);

<# foreach(var prop in properties) { #>
        <#= accessor #> <#= prop.Item2 #> <#= prop.Item1 #> { get; } 
<# } #>

        <#= classCtorAccessor #> <#= className #>(<#= ctorList #>)
        {
<# foreach(var prop in properties) { #>
            ValidateArgument(nameof(<#= PropToArg(prop.Item1) #>), <#= PropToArg(prop.Item1) #>);
            <#= prop.Item1 #> = <#= PropToArg(prop.Item1) #>;
<# } #>
        }
    }

    <#= accessor #> partial class <#=className#>Builder
    {
<# foreach(var prop in properties) { #>
        <#= accessor #> <#= prop.Item2 #> <#= prop.Item1 #> { get; set; } 
<# } #>

        <#= accessor #> <#= className #> Build<#= className #>()
        {
            var result = new <#= className #>(<#= string.Join(", ", properties.Select(p => p.Item1)) #>);
            return result;
        }
    }
}