/// <summary>
/// Retrieves the Unicode code point value that precedes the <paramref name="index"/>.
/// </summary>
/// <param name="text"></param>
/// <param name="index">The index to the <see cref="char"/> code unit within this object.</param>
/// <returns>The Unicode code point value.</returns>
/// <seealso cref="Character"/>
/// <seealso cref="Character.CodePointBefore(char[], int)"/>
public static int CodePointBefore(this StringBuilder text, int index)
{
if (index < 1 || index > text.Length)
{
throw new IndexOutOfRangeException(nameof(index));
}
return(Character.CodePointBefore(text, index));
}
public static int CodePointBefore(this string seq, int index)
{
return(Character.CodePointBefore(seq, index));
}