Bug#649679: [copyright-format] Clarify what distinguishes files and stand-alone license paragraphs.

[Jonathan Nieder <jrnieder@gmail.com>]

Hi,

Charles Plessy wrote:

> --- a/copyright-format/copyright-format.xml
> +++ b/copyright-format/copyright-format.xml
> @@ -172,11 +172,13 @@
>      <title>Paragraphs</title>
>      <para>
>        There are three kinds of paragraphs: the first one is called the
> -      <link linkend="header-paragraph">header paragraph</link>.
> +      <link linkend="header-paragraph">header paragraph</link>, similarly
> +      to the source package paragraphs in <filename>debian/control</filename>
> +      files.

You didn't introduce it, but I think the phrase starting with
"similarly to" here is problematic, since it makes the spec harder for
people outside Debian to understand and use, without adding much
clarity to compensate for that.  Could we remove it?

>                                                                   Every other
> -      paragraph is either a <link linkend="files-paragraph">Files</link>
> -      paragraph or a <link linkend="stand-alone-license-paragraph">stand-alone
> -      license</link> paragraph.  This is similar to source and binary package
> -      paragraphs in <filename>debian/control</filename> files.
>               Every other paragraph is either a <link linkend="files-paragraph">Files</link>
> +      paragraph, characterised by the presence of a <varname>Files</varname>
> +      field, or a <link linkend="stand-alone-license-paragraph">stand-alone license</link>
> +      paragraph, characterised by the presence of a <varname>License</varname>
> +      field and the absence of a <varname>Files</varname> field.

At first I thought License paragraphs consist of a
<varname>License</varname> field and nothing else, but then I
remembered that extra fields can be added to any paragraph.

So the mention of the absence of a Files field does seem to be needed
after all.  That would make:

	There are three kinds of paragraphs.  The first paragraph in
	the file is called the [header paragraph].  Every other paragraph
	is either a [Files] paragraph, characterised by the presence
	of a Files field, or a [stand-alone license] paragraph,
	characterised by the presence of a License field and absence
	of a Files field.