private static IColumn KeyValueMetadataFromMetadata <T>(ISchema schema, int col, string metadataName)
{
Contracts.AssertValue(schema);
Contracts.Assert(0 <= col && col < schema.ColumnCount);
var type = schema.GetMetadataTypeOrNull(metadataName, col);
Contracts.AssertValue(type);
Contracts.Assert(type.RawType == typeof(T));
ValueGetter <T> getter = (ref T val) => schema.GetMetadata(metadataName, col, ref val);
return(RowColumnUtils.GetColumn(MetadataUtils.Kinds.KeyValues, type, getter));
}
/// <summary>
/// Returns a row that is a deep in-memory copy of an input row. Note that inactive
/// columns are allowed in this row, and their activity or inactivity will be reflected
/// in the output row. Note that the deep copy includes a copy of the metadata as well.
/// </summary>
/// <param name="row">The input row</param>
/// <returns>A deep in-memory copy of the input row</returns>
public static IRow CloneRow(IRow row)
{
Contracts.CheckValue(row, nameof(row));
return(RowColumnUtils.GetRow(null,
Utils.BuildArray(row.Schema.ColumnCount, c => RowColumnUtils.GetColumn(row, c))));
}
