This is a mirror of http://www.vim.org/scripts/script.php?script_id=4364

:ExplainPattern {pattern}               or
:ExplainPattern {register}

        parse the given Vim {pattern} and print a line of help
        (with color) for each found pattern item.  Nested
        items get extra indent.

        A single-char argument is used as {register} argument:
                /	explain the last search pattern
                *	explain pattern from the clipboard
                a	explain pattern from register a


Example:  :ExplainPattern *

Register: *
Pattern: \C^\%(\\\%(@<.\|%[dxouU[(^$V#<>]\=\|z[1-9se(]\|@[>=!]\|_[[^$.]\=\|.\)\|.\)
  \C         match case while matching the pattern
  ^          match at start of line (or string)
  \%(        start of non-capturing group
  |   \\         literal string (1 atom(s))
  |   \%(        start of non-capturing group
  |   |   @<         literal string (2 atom(s))
  |   |   .          match any character
  |   | \|         OR branch
  |   |   %          literal string (1 atom(s))
  |   |   [dxouU[(^$V#<>] collection
  |   |   \=         (multi) zero or one of the preceding atom
  |   | \|         OR branch
  |   |   z          literal string (1 atom(s))
  |   |   [1-9se(]   collection
  |   | \|         OR branch
  |   |   @          literal string (1 atom(s))
  |   |   [>=!]      collection
  |   | \|         OR branch
  |   |   _          literal string (1 atom(s))
  |   |   [[^$.]     collection
  |   |   \=         (multi) zero or one of the preceding atom
  |   | \|         OR branch
  |   |   .          match any character
  |   \)         end of group
  | \|         OR branch
  |   .          match any character
  \)         end of group

2013 Jan 17