Infer T in CreateEnumerable<T> based in DataView schema

[luisquintanilla]

Problem

Today, when an IDataView is created using TextLoader, there's no need to create classes that define the schema.

var cols = new [] 
{
    new TextLoader.Column(name: "Text",dataKind:DataKind.String,index:47),
    new TextLoader.Column(
        name: "Categorical",
        dataKind: DataKind.String,
        source: new TextLoader.Range[] {
            new TextLoader.Range(19),
            new TextLoader.Range(20),
            new TextLoader.Range(21),
            new TextLoader.Range(50),
            new TextLoader.Range(59),
            new TextLoader.Range(71),
            new TextLoader.Range(83)}),
    new TextLoader.Column(name:"Label",dataKind:DataKind.String,2)
};

var dataLoader = ctx.Data.CreateTextLoader(columns:cols);
var idv = dataLoader.Load(path);

However, if I want to export the IDataView as an IEnumerable, I can't because I need to explicitly provide the type of IEnumerable<T>. If no classes have been created, I now need to go and create a new class just to export to an IEnumerable.

Proposed solution

Just like LoadFromEnumerable is able to infer and create an IDataView from IEnumerable<T>, CreateEnumerable should be able to infer T based on the DataView schema or bind to an object at runtime using dynamic.

ctx.Data.CreateEnumerable(idv,reuseRowObject:false,ignoreMissingColumns:false)

or

ctx.Data.CreateEnumerable<dynamic>(idv,reuseRowObject:false,ignoreMissingColumns:false)