## page was renamed from MathieuClabaut/Modelling
Some rant about general VCS requirements which will ''ideally'' end in a formal model matching Mercurial implementation (with hope it's not totally out of topic on the Mercurial wiki).

See this page as a pure intellectual exercise for now.

= Requirements =
Express from coarser detail to finer detail.

== High level requirements ==
 * Manage objects (will be files, directory, metadata...)
  * add object
  * remove object
  * modify object
 * keep immutable history (except for obliterating some content ?)
 * restore state from the past

== Intermediate level requirements ==
 * keep trace of who did the object management actions
 * add property to objects (comment, date, author..)
 * add property to history state (tags ?)

== Distributed requirements ==
 * Local history (will end in repository / branches)
  * clone
  * merge
 
== Other secondary requirements ==
 * narrow/shallow cloning ?
 
== Low levels requirements ==
Map to Mercurial commands/functions:
 * init, add, remove, backout, branch, clone, commit, copy, move, merge, push, pull, revert, tag

Map to Mercurial internals:
 * manifest, revlogs, 

= Formal Method =
 * B event (via rodin platform)