/// <summary>
/// Creates a <see cref="BlockExtension{T}"/>.
/// </summary>
/// <param name="blockRenderer">
/// <para>The renderer for rendering <see cref="IBlock"/>s as HTML.</para>
/// <para>This value can be <c>null</c>. An extension can parse <see cref="IBlock"/>s that aren't rendered.</para>
/// <para>If not <c>null</c>, this value is added to the <see cref="MarkdownPipeline"/>'s renderers.</para>
/// </param>
/// <param name="blockParsers">
/// <para>The <see cref="BlockParser"/>s for creating <see cref="IBlock"/>s from markdown.</para>
/// <para>This value can be empty. An extension can render <see cref="IBlock"/>s parsed by other extensions.</para>
/// <para>This value's elements are added to the <see cref="MarkdownPipeline"/>'s <see cref="BlockParser"/>s.</para>
/// </param>
protected BlockExtension(BlockRenderer <T> blockRenderer, IEnumerable <BlockParser> blockParsers)
{
_blockRenderer = blockRenderer;
_blockParsers = blockParsers;
}
/// <summary>
/// Creates a <see cref="BlockExtension{T}"/>.
/// </summary>
/// <param name="blockRenderer">
/// <para>The renderer for rendering <see cref="IBlock"/>s as HTML.</para>
/// <para>This value can be <c>null</c>. An extension can parse <see cref="IBlock"/>s that aren't rendered.</para>
/// <para>If not <c>null</c>, this value is added to the <see cref="MarkdownPipeline"/>'s renderers.</para>
/// </param>
/// <param name="blockParsers">
/// <para>The <see cref="BlockParser"/>s for creating <see cref="IBlock"/>s from markdown.</para>
/// <para>This value can be empty. An extension can render <see cref="IBlock"/>s parsed by other extensions.</para>
/// <para>This value's elements are added to the <see cref="MarkdownPipeline"/>'s <see cref="BlockParser"/>s.</para>
/// </param>
protected BlockExtension(BlockRenderer <T> blockRenderer, params BlockParser[] blockParsers)
{
_blockRenderer = blockRenderer;
_blockParsers = blockParsers;
}