c2rust-refactor 0.10.1

C2Rust refactoring tool implementation
Documentation 
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refactor:transform(
   function(transform, crate)
      return transform:match(
         function(mcx)
            pat = mcx:parse_stmts([[
$i:Ident = $start:Expr;
$'label:?Ident: while $cond:Expr {
    $body:MultiStmt;
    $incr:Stmt;
}]])
            lt_cond = mcx:parse_expr("$i < $end:Expr")
            le_cond = mcx:parse_expr("$i <= $end:Expr")

            i_plus_eq = mcx:parse_expr("$i += $step:Expr")
            i_eq_plus = mcx:parse_expr("$i = $i + $step:Expr")

            range_one_excl = mcx:parse_stmts("$'label: for $i in $start .. $end { $body; }")
            range_one_incl = mcx:parse_stmts("$'label: for $i in $start ..= $end { $body; }")
            range_step_excl = mcx:parse_stmts("$'label: for $i in ($start .. $end).step_by($step) { $body; }")
            range_step_incl = mcx:parse_stmts("$'label: for $i in ($start ..= $end).step_by($step) { $body; }")

            return mcx:fold_with(pat, crate,
               function(orig, mcx)
                  cond = mcx:get_expr("$cond")
                  if mcx:try_match(lt_cond, cond) then
                     range_excl = true
                  elseif mcx:try_match(le_cond, cond) then
                     range_excl = false
                  else
                     return orig
                  end

                  print("parsed cond")

                  incr = mcx:get_stmt("$incr")
                  incr = transform:get_ast(incr)
                  print(incr)
                  if (incr.kind == "Semi" or
                      incr.kind == "Expr") then
                     incr = incr.expr
                  else
                     return orig
                  end

                  if (not mcx:try_match(i_plus_eq, incr) and
                      not mcx:try_match(i_eq_plus, incr)) then
                     return orig
                  end

                  print("parsed incr")

                  step = mcx:get_expr("$step")
                  step = transform:get_ast(step)
                  if (step.type == "Expr" and step.kind == "Lit" and
                      step.value == 1) then
                     if range_excl then
                        repl_step = range_one_excl
                     else
                        repl_step = range_one_incl
                     end
                  else
                     if range_excl then
                        repl_step = range_step_excl
                     else
                        repl_step = range_step_incl
                     end
                  end

                  print("substituting")
                  return mcx:subst(repl_step)
               end
            )
         end
      )
   end
)
print("finished")