Penumbra/Penumbra/Util/ArrayExtensions.cs

using System;
using System.Collections.Generic;

namespace Penumbra
{
    public static class ArrayExtensions
    {
        public static void Swap< T >( this T[] array, int idx1, int idx2 )
        {
            var tmp = array[ idx1 ];
            array[ idx1 ] = array[ idx2 ];
            array[ idx2 ] = tmp;
        }

        public static void Swap< T >( this List< T > array, int idx1, int idx2 )
        {
            var tmp = array[ idx1 ];
            array[ idx1 ] = array[ idx2 ];
            array[ idx2 ] = tmp;
        }

        public static int IndexOf< T >( this T[] array, Predicate< T > match )
        {
            for( var i = 0; i < array.Length; ++i )
            {
                if( match( array[ i ] ) )
                {
                    return i;
                }
            }

            return -1;
        }

        public static void Swap< T >( this T[] array, T lhs, T rhs )
        {
            var idx1 = Array.IndexOf( array, lhs );
            if( idx1 < 0 )
            {
                return;
            }

            var idx2 = Array.IndexOf( array, rhs );
            if( idx2 < 0 )
            {
                return;
            }

            array.Swap( idx1, idx2 );
        }

        public static void Swap< T >( this List< T > array, T lhs, T rhs )
        {
            var idx1 = array.IndexOf( lhs );
            if( idx1 < 0 )
            {
                return;
            }

            var idx2 = array.IndexOf( rhs );
            if( idx2 < 0 )
            {
                return;
            }

            array.Swap( idx1, idx2 );
        }
    }
}