lib/solvers/solvers.rb in rulp-0.0.2 vs lib/solvers/solvers.rb in rulp-0.0.5

@@ -1,18 +1,26 @@
 class Solver
   def initialize(filename)
     @filename = filename
     @outfile = "/tmp/#{executable}-output.txt"
-    raise Exception.new("Couldn't find solver #{executable}!") if `which #{executable}`.length == 0
+    raise StandardError.new("Couldn't find solver #{executable}!") if `which #{executable}`.length == 0
     @solver_exists = true
   end
 
   def store_results(variables)
     puts "Not yet implemented"
   end
 
+  def executable
+    self.class.executable
+  end
+
   def solver_exists?
     @solver_exists || false
+  end
+
+  def self.exists?
+    return `which #{self.executable}`.length != 0
   end
 end
 
 require_relative 'cbc'
 require_relative 'scip'