feat(parser): supports literal decimal numbers

3 files changed, 23 insertions, 0 deletions

diff --git a/lib/elixir_math_parser.ex b/lib/elixir_math_parser.ex
index 4a96daf..286829e 100644
--- a/lib/elixir_math_parser.ex
+++ b/lib/elixir_math_parser.ex
@@ -4,11 +4,16 @@ defmodule ElixirMathParser do
   """
   alias ElixirMathParser.Math.Rational
   alias ElixirMathParser.Math.Calc
+  alias ElixirMathParser.Math.Conversion
 
   defp reduce_to_value({:int, _line, value}, _state) do
     {:ok, Rational.new(value)}
   end
 
+  defp reduce_to_value({:float, _line, value}, _state) do
+    {:ok, to_string(value) |> Conversion.literal_float_to_rational()}
+  end
+
   defp reduce_to_value({:var, line, var}, state) do
     if !Map.has_key?(state, var) do
       {:error, line, "value not found for " <> to_string(var)}
diff --git a/lib/math/Calc.ex b/lib/math/calc.ex
index 7dc5fcc..7dc5fcc 100644
--- a/lib/math/Calc.ex
+++ b/lib/math/calc.ex
diff --git a/lib/math/conversion.ex b/lib/math/conversion.ex
new file mode 100644
index 0000000..65ddf8f
--- /dev/null
+++ b/lib/math/conversion.ex
@@ -0,0 +1,18 @@
+defmodule ElixirMathParser.Math.Conversion do
+  alias ElixirMathParser.Math.Rational
+
+  def literal_float_to_rational(value) do
+    {int, dec} = Integer.parse(value)
+
+    String.graphemes(dec)
+    |> Enum.reduce(Rational.new(int), fn v, acc ->
+      if v != "." do
+        num = Rational.numerator(acc) * 10
+        den = Rational.denominator(acc) * 10
+        Rational.new(num + String.to_integer(v), den)
+      else
+        acc
+      end
+    end)
+  end
+end