Nested .STATIC Sections

[cspiel]

.STATIC sections nested inside sections are interesting.

• Problem 1: The documentation says (in section 4.15.1) that plain
  .STATIC targets export all of their variables. However, the
  export appears incomplete: we can access such a variable, but a
  function defined inside the same .STATIC block does not retrieve
  the variable's contents. No error is emitted, though.

• Problem 2: If we export a function from a section and this
  function binds a variable from a nested .STATIC section, the
  binding dissappears outside of the defining section.

Example program (see comments for locations of Problem 1 and
Problem 2):

##  Uncomment the next line to see dynamic binding in action.
#public.b = $'top-level def'


section
        .STATIC:  # `.MEMO' works, too ;-)
                a = $'sectioned, static def'
                fa() =
                        return $(a)

                ##  Use `a' and `fa' inside of static block.
                println($"[section] [static]  a = <$(a)>")
                println($"[section] [static]  fa: <$(fa)>")


        ##  Use `a' and `fa' outside of static block.
        println($"[section]           a = <$(a)>")

        ##  Problem 1: No error here, but "empty" result.  We have
        ##  just proven that `a' is visible, so `fa' ought to return
        ##  `a's contents.
        println($"[section]           fa: <$(fa)>")


        ##  Copy static `a' to non-static `b'.
        b = $(a)
        println($"[section]           b = <$(b)>")

        ga() =
                return $(a)
        gb() =
                return $(b)


        ##  Use `ga' and `gb' in the same scope as their definitions.
        println($"[section]           ga: <$(ga)>")
        println($"[section]           gb: <$(gb)>")

        ##  `unbound variable' error triggered outside of `section'
        ##  disappears if we add `a' to the export list.  No need to
        ##  export `b', though because of dynamic binding.
        export ga gb


##  Sectioned `b' has been "captured" by `gb'.
println($"gb: <$(gb)>")

##  Problem 2: The next line fails with `unbound variable: public.a'.
println($"ga: <$(ga)>")

Output of osh example.om:

[section] [static]  a = <sectioned, static def>
[section] [static]  fa: <sectioned, static def>
[section]           a = <sectioned, static def>
[section]           fa: <>
[section]           b = <sectioned, static def>
[section]           ga: <sectioned, static def>
[section]           gb: <sectioned, static def>
gb: <sectioned, static def>
*** omake error:
   File example.om: line 30, characters 23-27
   unbound variable: public.a