## Presentation of the Addendum

Here you will find several pieces of additional documentation for the Coq Reference Manual. Each of this chapters is concentrated on a particular topic, that should interest only a fraction of the Coq users : that's the reason why they are apart from the Reference Manual.

Extended pattern-matching
  This chapter details the use of generalized pattern-matching. It is contributed by Cristina Cornes and Hugo Herbelin
Implicit coercions
  This chapter details the use of the coercion mechanism. It is contributed by Amokrane Saïbi.
Proof of imperative programs
  This chapter explains how to prove properties of annotated programs with imperative features. It is contributed by Jean-Christophe Filliâtre
Program extraction
  This chapter explains how to extract in practice ML files from Fw terms. It is contributed by Jean-Christophe Filliâtre and Pierre Letouzey.
Omega
  `Omega`, written by Pierre Crégut, solves a whole class of arithmetic problems.
Program
  The `Program` technology intends to inverse the extraction mechanism. It allows the developments of certified programs in Coq. This chapter is due to Catherine Parent. This feature is not available in Coq version 7.
The `Ring` tactic
  This is a tactic to do AC rewriting. This chapter explains how to use it and how it works. The chapter is contributed by Patrick Loiseleur.
The `Setoid_replace` tactic
  This is a tactic to do rewriting on types equipped with specific (only partially substitutive) equality. The chapter is contributed by Clément Renard.