protobuf/csharp/src/Google.Protobuf/Freezable.cs

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#endregion

using System;

namespace Google.Protobuf
{
    /// <summary>
    /// Extension methods for <see cref="IFreezable"/> types.
    /// </summary>
    public static class Freezable
    {
        /// <summary>
        /// Throws an <see cref="InvalidOperationException"/> if <paramref name="target"/>
        /// is frozen.
        /// </summary>
        /// <remarks>
        /// This is a convenience methods that freezable types can call before all
        /// mutations, to protect frozen objects.
        /// </remarks>
        public static void CheckMutable(this IFreezable target)
        {
            if (target.IsFrozen)
            {
                throw new InvalidOperationException("Attempt to mutate frozen object");
            }
        }
    }
}