Class: Regaxp::Eiruc

Inherits:
Object
  • Object
show all
Defined in:
lib/regaxp/eiruc.rb

Overview

Parses and execute Reverse Polish notation expressions.

Defined Under Namespace

Classes: UndefinedFun

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Eiruc

Returns a new instance of Eiruc.



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# File 'lib/regaxp/eiruc.rb', line 10

def initialize
  @functions = {}
end

Instance Method Details

#evaluate(expression) ⇒ Object 



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# File 'lib/regaxp/eiruc.rb', line 14

def evaluate(expression)
  expression.reduce([]) { |stack, token| process_token token, stack }[0]
end

#fun(name, fun_object = nil, &fun_body) ⇒ Object 



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# File 'lib/regaxp/eiruc.rb', line 18

def fun(name, fun_object = nil, &fun_body)
  # TODO: validates fun_object is a callable
  # TODO: validates arity?
  functions[name.to_sym] = fun_body || fun_object
end