Adding Fixnum#[] (bits as element references)

http://www.ruby-doc.org/core-1.9.3/Fixnum.html#method-i-5B-5D
opal · Feb 5, 2014 · 85220f3 · 85220f3
1 parent d21fba0
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diff --git a/opal/corelib/numeric.rb b/opal/corelib/numeric.rb
@@ -195,6 +195,14 @@ def >>(count)
     `self >> #{count.to_int}`
   end
 
+  def [](bit)
+    bit = Opal.coerce_to! bit, Integer, :to_int
+    min = -(2**30)
+    max =  (2**30) - 1
+
+    `(#{bit} < #{min} || #{bit} > #{max}) ? 0 : (self >> #{bit}) % 2`
+  end
+
   def +@
     `+self`
   end

diff --git a/spec/opal/rubyspecs b/spec/opal/rubyspecs
@@ -18,6 +18,7 @@ core/fixnum/abs_spec
 core/fixnum/case_compare_spec
 core/fixnum/comparison_spec
 core/fixnum/equal_value_spec
+core/fixnum/element_reference_spec
 core/fixnum/even_spec
 core/fixnum/gt_spec
 core/fixnum/gte_spec