public virtual void Destroy(object O)
        {
            try
            {
                m_container.Mockery.VerifyAllExpectationsHaveBeenMet()
+;
            }
            finally
            {
                m_container = null;
            }
        }
[download]

Ok... first problem I see (besides the params regexp already pointed out... is your not_method regexp piece...

you didn't put it in a container, so your pipes aren't doing what you expect...

if ($line =~ /^\W*(?:$not_method)/) {
[download]

That'll work better.

Update a \b at the end would also help make sure you don't match a string starting with as or if etc...

if ($line =~ /^\W*(?:$not_method)\b/) {
[download]

                - Ant
                - Some of my best work - (1 2 3)

And what should it look like once converted? When I run it I see it getting the copyright and nothing else changes.

                - Ant
                - Some of my best work - (1 2 3)

It should look like:

                /// <summary>
               /// public virtual void Destroy(object O)
                /// </summary>
                /// <param name = "O">object</param>
        public virtual void Destroy(object O)
        {
            try
            {
                m_container.Mockery.VerifyAllExpectationsHaveBeenMet()
+;
            }
            finally
            {
                m_container = null;
            }
        }
[download]

Also, if the method dataset has no arguments, running it inserts a header (just the lines for summary) and appends another empty pair of parens to the declaration line. In other words, this as the dataset:

        public virtual void Destroy()
        {
            try
            {
                m_container.Mockery.VerifyAllExpectationsHaveBeenMet()
+;
            }
            finally
            {
                m_container = null;
            }
        }
[download]

results in this in the output:

        /// <summary>
        ///  public virtual void Destroy()
        /// </summary> 
        public virtual void Destroy()()
        {
            try
            {
                m_container.Mockery.VerifyAllExpectationsHaveBeenMet()
+;
            }
            finally
            {
                m_container = null;
            }
        }
[download]