Merge branch 'master' of ssh://git.eclipse.org/gitroot/koneki/org.eclipse.koneki...

[metalua.git] / junk / hygienic2.lua

diff --git a/junk/hygienic2.lua b/junk/hygienic2.lua
deleted file mode 100644 (file)
index d0ca8c3..0000000
--- a/junk/hygienic2.lua
+++ /dev/null
@@ -1,101 +0,0 @@
---------------------------------------------------------------------------------
---
--- (c) Fabien Fleutot 2007, published under the MIT license.
---
---
--- API:
--- ----
--- * freevars.block(ast)
--- * freevars.expr(ast)
--- * freevars.stat(ast)
---
---------------------------------------------------------------------------------
-
-require 'std'
-require 'walk'
-require 'freevars'
-
--{ extension 'match' }
-
---------------------------------------------------------------------------------
--- Return the string->boolean hash table of the names of all free variables
--- in 'term'. 'kind' is the name of an entry in module 'walk', presumably
--- one of 'expr', 'stat' or 'block'.
---------------------------------------------------------------------------------
-local function alpha (kind, term)
-   local cfg = { expr  = { }, stat  = { }, block = { } }
-
-   -----------------------------------------------------------------------------
-   -- Monkey-patch the scope add method, so that it associates a unique name
-   -- to bound vars.
-   -----------------------------------------------------------------------------
-   local scope = scope:new()
-   function scope:add(vars)
-      for v in values(vars) do self.current[v] = mlp.gensym(v) end
-   end
-      
-   -----------------------------------------------------------------------------
-   -- Check identifiers; add functions parameters to scope
-   -----------------------------------------------------------------------------
-   function cfg.expr.down(x)
-      match x with
-      | `Splice{...} -> return 'break' -- don't touch user parts
-      | `Id{ name } ->
-         local alpha = scope.current[name]
-         if alpha then x[1] = alpha end
-      | `Function{ params, _ } -> scope:push(); scope:add (params)
-      | _ -> -- pass
-      end
-   end
-
-   -----------------------------------------------------------------------------
-   -- Close the function scope opened by 'down()'
-   -----------------------------------------------------------------------------
-   function cfg.expr.up(x)      
-      match x with `Function{...} -> scope:pop() | _ -> end
-   end
-
-   -----------------------------------------------------------------------------
-   -- Create a new scope and register loop variable[s] in it
-   -----------------------------------------------------------------------------
-   function cfg.stat.down(x)
-      match x with
-      | `Splice{...}           -> return 'break'
-      | `Forin{ vars, ... }    -> scope:push(); scope:add(vars)
-      | `Fornum{ var, ... }    -> scope:push(); scope:add{var}
-      | `Localrec{ vars, ... } -> scope:add(vars)
-      | `Repeat{ block, cond } -> -- 'cond' is in the scope of 'block'
-         scope:push()
-         for s in values (block) do walk.stat(cfg)(s) end -- no new scope
-         walk.expr(cfg)(cond)
-         scope:pop()
-         return 'break' -- No automatic walking of subparts
-      | _ -> -- pass
-      end
-   end
-
-   -----------------------------------------------------------------------------
-   -- Close the scopes opened by 'up()'
-   -----------------------------------------------------------------------------
-   function cfg.stat.up(x)
-      match x with
-      | `Forin{ ... } | `Fornum{ ... } -> scope:pop() -- `Repeat has no up().
-      | `Local{ vars, ... }            -> scope:add(vars)
-      | _ -> -- pass
-      end
-   end
-
-   -----------------------------------------------------------------------------
-   -- Create a separate scope for each block
-   -----------------------------------------------------------------------------
-   function cfg.block.down() scope:push() end
-   function cfg.block.up()   scope:pop()  end
-
-   walk[kind](cfg)(term)
-   return freevars
-end
-
---------------------------------------------------------------------------------
--- A wee bit of metatable hackery. Just couldn't resist, sorry.
---------------------------------------------------------------------------------
-freevars = setmetatable ({ scope=scope }, { __index = |_, k| |t| fv(k, t) })