diff options
Diffstat (limited to 'lib/msgthr.rb')
| -rw-r--r-- | lib/msgthr.rb | 82 |
1 files changed, 73 insertions, 9 deletions
diff --git a/lib/msgthr.rb b/lib/msgthr.rb index f8b5896..ea63731 100644 --- a/lib/msgthr.rb +++ b/lib/msgthr.rb @@ -2,6 +2,18 @@ # License: GPL-2.0+ <https://www.gnu.org/licenses/gpl-2.0.txt> # Non-recursive, container-agnostic message threading. +# +# Usage is typically: +# +# * use Msgthr.new to create a new object +# * use Msgthr#add! for every message you have +# * use Msgthr#thread! to perform threading operations +# * optionally, use Msgthr#order! to sort messages +# * use Msgthr#walk_thread to iterate through the threaded tree +# +# See https://80x24.org/msgthr/README for more info +# You may email us publically at mailto:msgthr-public@80x24.org +# Archives are at https://80x24.org/msgthr-public/ class Msgthr # an Array of root (parent-less) messages, only populated after @@ -20,20 +32,68 @@ class Msgthr @id_table.clear end - # Threads the message - # This does not sort + # Performs threading on the messages and returns the rootset + # (set of message containers without parents). + # + # Call this after all #add operations are complete. + # This does not sort, use #order! if sorting is necessary. def thread! ret = @rootset @id_table.each_value { |cont| ret << cont if cont.parent.nil? }.clear ret end + # Performs an in-place sort on messages after thread! + # This is optional and intended to be called this only after #thread! + # + # This takes a block which yields an array of Msgthr::Container + # objects for sorting. + # + # To sort by unique +mid+ identifiers for each container: + # + # msgthr.order! { |ary| ary.sort_by!(&:mid) } + # + # If your opaque message pointer contains a +time+ accessor which gives + # a Time object: + # + # msgthr.order! do |ary| + # ary.sort_by! do |cont| # Msgthr::Container + # cur = cont.topmost + # cur ? cur.msg.time : Time.at(0) + # end + # end + # + # Note, using Msgthr::Container#topmost is NOT necessary when accessing + # Msgthr::Container#mid, as any known missing messages (ghosts) + # will still have a +mid+. However, Msgthr::Container#topmost is + # necessary if accessing Msgthr::Container#msg. def order! yield @rootset - @rootset.each { |cont| cont.order! { |children| yield(children) } } + @rootset.each do |cont| + # this calls Msgthr::Container#order!, which is non-recursive + cont.order! { |children| yield(children) } + end end - # non-recursively walk a thread + # non-recursively walk a set of messages after #thread! + # (and optionally, #order!) + # + # This takes a block and yields 3 elements to it: +|level, container, index|+ + # for each message container. + # + # * +level+ is the current depth within the walk (non-negative Integer) + # * +container+ is the Msgthr::Container object + # * +index+ is the offset of the container within its level (starting at 0) + # + # To display the subject of each message with indentation, + # assuming your +msg+ pointer has a +subject+ field: + # + # msgthr.walk_thread do |level, container, index| + # msg = container.msg + # subject = msg ? msg.subject : "[missing: <#{container.mid}>]" + # indent = ' ' * level + # printf("#{indent} % 3d. %s\n", index, subject) + # end def walk_thread i = -1 q = @rootset.map { |cont| [ 0, cont, i += 1 ] } @@ -49,20 +109,24 @@ class Msgthr # Adds a message to prepare a Msgthr object for threading. # # * +mid+ is a unique identifier for the message in a given thread. + # It is typically a String or Integer, but may be anything usable + # as a Hash key in Ruby. # - # * +refs+ should be an Array of unique identifiers. For mail and - # news messages, this is usually the parsed result of the - # "References:" header. Order should be oldest to newest + # * +refs+ should be an Array of unique identifiers belonging + # to ancestors of the current message. + # For mail and news messages, this is usually the parsed result + # of the "References:" header. Order should be oldest to newest # in terms of ancestry, with the last element being the # immediate parent of the given message. # - # This is +nil+ for messages with no parent. + # This is +nil+ for messages with no parent (root messages). # # * +msg+ is an opaque object which typically contains a # Mail or Tmail object for handling mail. # # If +mid+ is a String, it is recommended to freeze the string before - # calling this method to avoid wasting memory on hash keys. + # calling this method to avoid wasting memory on hash keys. Likewise + # is true for any String objects in +refs+. def add(mid, refs, msg) cur = @id_table[mid] ||= Msgthr::Container.new(mid) cur.msg = msg |