Automatically supply the origin URL in svn merge

Hello, all

Why does even the basic sync-merging require that the user
specify the source URL, as in:

  svn merge ^/project/trunk

I think this requirement is redundant because SVN know
exactly from which original original directory the branch
was created by svn cp. Will you consider simplifying the
basic merge syntax to:

  svn merge
  svn merge <local_path>

so that SVN shall supply the origin URL automatically? Or
am I wrong, and my proposal makes no sense?

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