LMCS-Paper/Paper.thy
changeset 3131 3e37322465e2
parent 3130 8fc6b801985b
child 3154 990f066609c9
equal deleted inserted replaced
3130:8fc6b801985b 3131:3e37322465e2
   144   @{text xs} (seen as set) such that @{text "\<sigma>(T') = T"}.
   144   @{text xs} (seen as set) such that @{text "\<sigma>(T') = T"}.
   145   The problem with this definition is that we cannot follow the usual proofs 
   145   The problem with this definition is that we cannot follow the usual proofs 
   146   that are by induction on the type-part of the type-scheme (since it is under
   146   that are by induction on the type-part of the type-scheme (since it is under
   147   an existential quantifier and only an alpha-variant). The representation of 
   147   an existential quantifier and only an alpha-variant). The representation of 
   148   type-schemes using iterations of single binders 
   148   type-schemes using iterations of single binders 
   149   prevents us from directly ``unbinding'' the bound thye-variables and the type-part. 
   149   prevents us from directly ``unbinding'' the bound type-variables and the type-part. 
   150   The purpose of this paper is to introduce general binders, which 
   150   The purpose of this paper is to introduce general binders, which 
   151   allow us to represent type-schemes so that they can bind multiple variables at once
   151   allow us to represent type-schemes so that they can bind multiple variables at once
   152   and as a result solve this problem.
   152   and as a result solve this problem.
   153   The need of iterating single binders is also one reason
   153   The need of iterating single binders is also one reason
   154   why Nominal Isabelle and similar theorem provers that only provide
   154   why Nominal Isabelle and similar theorem provers that only provide
  2572   a corresponding reasoning infrastructure. However we have found out that 
  2572   a corresponding reasoning infrastructure. However we have found out that 
  2573   telescopes seem to not easily representable in our framework. The reason is that
  2573   telescopes seem to not easily representable in our framework. The reason is that
  2574   we need to be able to lift our @{text bn}-function to alpha-equated lambda-terms.
  2574   we need to be able to lift our @{text bn}-function to alpha-equated lambda-terms.
  2575   This requires restrictions, which class with the `global' scope of binders in
  2575   This requires restrictions, which class with the `global' scope of binders in
  2576   telescopes. They can
  2576   telescopes. They can
  2577   be represented in the framework desribed in \cite{WeirichYorgeySheard11} using an extension of
  2577   be represented in the framework described in \cite{WeirichYorgeySheard11} using an extension of
  2578   the usual locally-nameless representation. 
  2578   the usual locally-nameless representation. 
  2579 
  2579 
  2580   \begin{figure}[p]
  2580   \begin{figure}[p]
  2581   \begin{boxedminipage}{\linewidth}
  2581   \begin{boxedminipage}{\linewidth}
  2582   \small
  2582   \small