Ruby: add step8_macros

1 files changed, 5 insertions, 0 deletions

diff --git a/ruby/core.rb b/ruby/core.rb
index 268ebad..824b59b 100644
--- a/ruby/core.rb
+++ b/ruby/core.rb
@@ -14,6 +14,11 @@ $core_ns = {
     :/ =>         lambda {|a,b| a / b},
     :list =>      lambda {|*a| List.new a},
     :list? =>     lambda {|*a| a[0].is_a? List},
+    :cons =>      lambda {|a,b| List.new(b.clone.insert(0,a))},
+    :concat =>    lambda {|*a| List.new(a && a.reduce(:concat) || [])},
+    :nth =>       lambda {|a,b| a[b]},
+    :first =>     lambda {|a| a[0]},
+    :rest =>      lambda {|a| List.new(a.size > 0 && a.drop(1) || [])},
     :empty? =>    lambda {|a| a.size == 0},
     :count =>     lambda {|a| a.size},
 }