osu.Framework/Graphics/Containers/CompositeDrawable.cs
/// <summary>
/// The index of a given child within <see cref="InternalChildren"/>.
/// </summary>
/// <returns>
/// If the child is found, its index. Otherwise, the negated index it would obtain
/// if it were added to <see cref="InternalChildren"/>.
/// </returns>
The index of a given child within .
The index of a given child within .
protected internal int IndexOfInternal(Drawable drawable)
        {
            int index = internalChildren.IndexOf(drawable);
            if (index >= 0 && internalChildren[index].ChildID != drawable.ChildID)
                throw new InvalidOperationException($@"A non-matching {nameof(Drawable)} was returned. Please ensure {GetType()}'s {nameof(Compare)} override implements a stable sort algorithm.");
            return index;
        }
protected internal int IndexOfInternal ( Drawable drawable ) { int index = internalChildren . IndexOf ( drawable ) ; if ( index >= 0 && internalChildren [ index ] . ChildID != drawable . ChildID ) throw new InvalidOperationException ( $@" A non-matching  { nameof ( Drawable ) }  was returned. Please ensure  { GetType ( ) } 's  { nameof ( Compare ) }  override implements a stable sort algorithm. " ) ; return index ; }
The index of a given child within .
The index of a given child within .
If the child is found, its index. Otherwise, the negated index it would obtain
if it were added to .
If the child is found its index . Otherwise the negated index it would obtain if it were added to .
drawable
Drawable