Class: Campa::Evaler

Inherits:
Object
  • Object
show all
Defined in:
lib/campa/evaler.rb

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Evaler

Returns a new instance of Evaler.



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# File 'lib/campa/evaler.rb', line 3

def initialize
  @printer = Printer.new
end

Instance Method Details

#call(expression, env = {}) ⇒ Object 



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# File 'lib/campa/evaler.rb', line 7

def call(expression, env = {})
  context = self.context(env)

  case expression
  when Numeric, TrueClass, FalseClass, NilClass, String, ::Symbol, List::EMPTY
    expression
  when Symbol
    resolve(expression, context)
  when List
    invoke(expression, context)
  end
end

#eval(reader, env = {}) ⇒ Object 



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# File 'lib/campa/evaler.rb', line 20

def eval(reader, env = {})
  context = self.context(env)

  result = nil
  while (token = reader.next)
    result = call(token, context)
  end
  result
end