/// <summary>
/// Performs the Boyer-Moore-Horspool string-search, finding the starting index of the <paramref name="table"/> pattern if found in <paramref name="source"/>.
/// </summary>
/// <param name="source">The <see cref="ReadOnlySpan{T}"/> of <see cref="Char"/> to search in.</param>
/// <param name="table">The <see cref="HorspoolTable"/> of the pattern to search for.</param>
/// <returns>The index at which the pattern was found to start; -1 if not found.</returns>
public static Int32 Horspool(ReadOnlySpan <Char> source, HorspoolTable table)
{
Guard.NotNull(table, nameof(table));
ReadOnlySpan <Char> candidate;
Int32 skip = 0;
while (source.Length - skip >= table.Length)
{
candidate = source.Slice(skip, table.Length);
if (candidate == table)
{
return(skip);
}
skip += table[source[skip + table.Length - 1]];
}
return(-1);
}
/// <summary>
/// Performs the Boyer-Moore-Horspool string-search, finding the starting index of the <paramref name="pattern"/> if found in <paramref name="source"/>.
/// </summary>
/// <param name="source">The <see cref="String"/> to search in.</param>
/// <param name="pattern">The <see cref="String"/> to search for.</param>
/// <param name="table">The <see cref="HorspoolTable"/> for <paramref name="pattern"/>.</param>
/// <returns>The index at which <paramref name="pattern"/> was found to start; -1 if not found.</returns>
public static Int32 Horspool(String source, String pattern, out HorspoolTable table)
{
Guard.NotNull(source, nameof(source));
Guard.NotNull(pattern, nameof(pattern));
return(Horspool(source.AsSpan(), pattern.AsSpan(), out table));
}
/// <summary>
/// Performs the Boyer-Moore-Horspool string-search, finding the starting index of the <paramref name="table"/> pattern if found in <paramref name="source"/>.
/// </summary>
/// <param name="source">The <see cref="String"/> to search in.</param>
/// <param name="table">The <see cref="HorspoolTable"/> of the pattern to search for.</param>
/// <returns>The index at which the pattern was found to start; -1 if not found.</returns>
public static Int32 Horspool(String source, HorspoolTable table)
{
Guard.NotNull(source, nameof(source));
Guard.NotNull(table, nameof(table));
return(Horspool(source.AsSpan(), table));
}
/// <summary>
/// Performs the Boyer-Moore-Horspool string-search, finding the starting index of the <paramref name="pattern"/> if found in <paramref name="source"/>.
/// </summary>
/// <param name="source">The <see cref="ReadOnlySpan{T}"/> of <see cref="Char"/> to search in.</param>
/// <param name="pattern">The <see cref="ReadOnlySpan{T}"/> of <see cref="Char"/> to search for.</param>
/// <param name="table">The <see cref="HorspoolTable"/> for <paramref name="pattern"/>.</param>
/// <returns>The index at which <paramref name="pattern"/> was found to start; -1 if not found.</returns>
public static Int32 Horspool(ReadOnlySpan <Char> source, ReadOnlySpan <Char> pattern, out HorspoolTable table)
{
table = new HorspoolTable(pattern);
return(Horspool(source, table));
}
/// <summary>
/// Performs the Boyer-Moore-Horspool string-search, finding the starting index of the <paramref name="pattern"/> if found in <paramref name="source"/>.
/// </summary>
/// <param name="source">The <see cref="ReadOnlySpan{T}"/> of <see cref="Char"/> to search in.</param>
/// <param name="pattern">The <see cref="String"/> to search for.</param>
/// <param name="table">The <see cref="HorspoolTable"/> for <paramref name="pattern"/>.</param>
/// <returns>The index at which <paramref name="pattern"/> was found to start; -1 if not found.</returns>
public static Int32 Horspool(ReadOnlySpan <Char> source, String pattern, out HorspoolTable table)
{
Guard.NotNull(pattern, nameof(pattern));
return(Horspool(source, pattern.AsSpan(), out table));
}
/// <summary>
/// Performs the Boyer-Moore-Horspool string-search, finding the starting index of the <paramref name="pattern"/> if found in <paramref name="source"/>.
/// </summary>
/// <param name="source">The <see cref="String"/> to search in.</param>
/// <param name="pattern">The <see cref="ReadOnlySpan{T}"/> of <see cref="Char"/> to search for.</param>
/// <param name="table">The <see cref="HorspoolTable"/> for <paramref name="pattern"/>.</param>
/// <returns>The index at which <paramref name="pattern"/> was found to start; -1 if not found.</returns>
public static Int32 Horspool(String source, ReadOnlySpan <Char> pattern, out HorspoolTable table)
{
Guard.NotNull(source, nameof(source));
return(Horspool(source.AsSpan(), pattern, out table));
}
