Hello,

As explained in its commit message, the following patch is an attempt at
simplifying `org-show-context' configuration by offering a set of
5 predefined views to choose from instead of setting 4 different
variables (`org-show-following-heading', `org-show-siblings',
`org-show-entry-below' and `org-show-hierarchy-above'). These views are

  minimal        show current headline, and entry below if needed
  local          show current headline, entry below and next headline
  lineage        show direct ancestors and all siblings of current headline;
                 show entry only if required
  canonical      show direct ancestors and all of their siblings; show entry
                 only if required
  full           show direct ancestors, all their siblings and entry

To sum it up, if original buffer is

  * H1
  * H2
  ** Sub 1
  ** Sub 2
  *** Sub sub 1
  *** Sub sub 2
      Text
  *** Sub sub 3
  *** Sub sub 4
  ** Sub 3

and match is on "Text", minimal is

  * H1
  * H2
    * Sub sub 2
      Text

`local' is

  * H1
  * H2
  *** Sub sub 2
      Text
  *** Sub sub 3

`lineage' is

  * H1
  * H2
  ** Sub 2
  *** Sub sub 1
  *** Sub sub 2
      Text
  *** Sub sub 3
  *** Sub sub 4

`canonical' and `full' are

  * H1
  * H2
  ** Sub 1
  ** Sub 2
  *** Sub sub 1
  *** Sub sub 2
      Text
  *** Sub sub 3
  *** Sub sub 4
  ** Sub 3

Note that neither `canonical' nor `full' are possible to obtain with the
4 original variables.

"if required"/"if needed" means the entry will only be shown if point is
within the entry (i.e., not on the headline). Thus, for example,
`canonical' and `full' only differ when match is on a headline, since
only latter will show the entry.

I think this is enough, but I can add more views if needed.

WDYT?


Regards,

-- 
Nicolas Goaziou                                                0x80A93738