1  # coding: utf-8
   2  # frozen_string_literal: true
   3 
   4 
   5 
   6  module Umu
   7 
   8  module AbstractSyntax
   9 
  10  module Core
  11 
  12  module Declaration
  13 
  14  class MutualRecursive < Abstract
  15      attr_reader :bindings
  16 
  17 
  18      def initialize(loc, bindings)
  19          ASSERT.kind_of loc,         LOC::Entry
  20          ASSERT.kind_of bindings,    ::Hash
  21          ASSERT.assert (bindings.size >= 2), bindings.inspect
  22 
  23          super(loc)
  24 
  25          @bindings = bindings
  26      end
  27 
  28 
  29      def to_s
  30          format(
  31              "%%VAL %%REC %s",
  32              self.bindings.map { |sym, target|
  33                  format "%s = %s", sym.to_s, target.lam_expr.to_s
  34              }.join(" %%AND ")
  35          )
  36      end
  37 
  38 
  39      def pretty_print(q)
  40          q.text '%VAL %REC '
  41 
  42          fst_sym, fst_target = self.bindings.first
  43          __pretty_print_binding__ q, fst_sym, fst_target
  44 
  45          not_fst_bindings = self.bindings.reject { |sym, _| sym == fst_sym }
  46          not_fst_bindings.each do |sym, target|
  47              q.breakable ''
  48 
  49              q.text ' %AND '
  50              __pretty_print_binding__ q, sym, target
  51          end
  52      end
  53 
  54 
  55  private
  56 
  57      def __pretty_print_binding__(q, sym, target)
  58              q.text format("%s = ", sym.to_s)
  59              PRT.group q do
  60                  q.pp target
  61              end
  62      end
  63 
  64 
  65      def __evaluate__(env)
  66          ASSERT.kind_of env, E::Entry
  67 
  68          env.va_extend_bindings self.bindings
  69      end
  70  end
  71 
  72 
  73 
  74  module_function
  75 
  76      def make_mutual_recursive(loc, bindings)
  77          ASSERT.kind_of loc,         LOC::Entry
  78          ASSERT.kind_of bindings,    ::Hash
  79 
  80          MutualRecursive.new(loc, bindings.freeze).freeze
  81      end
  82 
  83  end # Umu::AbstractSyntax::Core::Declaration
  84 
  85  end # Umu::AbstractSyntax::Core
  86 
  87  end # Umu::AbstractSyntax
  88 
  89  end # Umu