[MacPorts] #71612: Guide section 5.3.2. Installation Phase Keywords is mistitled, and should explain keyword semantics better

[MacPorts]

#71612: Guide section 5.3.2. Installation Phase Keywords is mistitled, and should
explain keyword semantics better
-------------------------+--------------------
 Reporter:  JDLH         |      Owner:  (none)
     Type:  enhancement  |     Status:  new
 Priority:  Normal       |  Milestone:
Component:  guide        |    Version:  2.10.5
 Keywords:               |       Port:
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 Presently the [https://guide.macports.org/#reference.phases.installation
 Guide, section 5.3.2. "Installation Phase Keywords"] does not in fact
 explain keywords which affect the installation phase. It introduces some
 semantics of keywords, and it explains the behaviour of Keyword List
 Modifiers like `-append`, and of Keyword Argument Modifiers like
 `.pre_args`. So, I propose that this section be retitled something like,
 "About Keywords".

 The current section 5.3.2 does not appear to have any content about
 installation phase keywords. If such keywords exist, I suggest that they
 be documented in a new section, after
 [https://guide.macports.org/#reference.phases.destroot 5.3.10. "Destroot
 Phase Keywords"], and based on that section's structure.

 A [https://github.com/macports/macports-
 guide/pull/70#issuecomment-2558203424 comment on Pull Request #70 "guide:
 additions for subport"] says, "Please explain the rules when there are
 apparent conflicting definitions, such as configure.args in example-sub1.
 Do not assume that the reader is confident in basic TCL. (That would be
 me, for example.)" The comment refers to a subport which repeats a keyword
 in the main port definition, but with a different value. For instance,
 what is the result if a port file boils down to the sequence,
 {{{
 configure.args             --bbb
 configure.args             --ddd</programlisting>
 }}}
 I suspect that the value of `--bbb` is completely replaced by the value of
 `--ddd</programlisting>`, but I do not see the Guide saying so. I suggest
 documenting these rules in the retitled section 5.3.2.

 According to [https://github.com/macports/macports-
 guide/blame/master/guide/xml/portfile-phase.xml#L165 gitblame of this
 section's source], as best I understand it, the current title and content
 of this section was transferred into the Guide from a macports man page
 back in 2007, and has not been rewritten since.

-- 
Ticket URL: <https://trac.macports.org/ticket/71612>
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