Class: ErlangAdapter

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

Overview

Erlang specific commands and evaluator

Instance Method Summary collapse

Constructor Details

#initialize(host = "localhost", port = 9900) ⇒ ErlangAdapter

Erlang host server name (the default is “localhost”)

Port

Erlang server port number (the default is “9900”)



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# File 'lib/erlang_adapter.rb', line 28

def initialize(host="localhost", port=9900)
  @host, @port = host, port
end

Instance Method Details

#eval(command) ⇒ Object

whitespace to differentiate between floats and EOL.



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# File 'lib/erlang_adapter.rb', line 34

def eval(command)
  socket = TCPSocket.new(@host, @port)
  
   # There has to be a trailing space at the end of a command for erl_scan:tokens
   # to process the string.
   command << '.' if command.scan(/\.\w*/).empty?
  command << " "
  socket.write(command)
  socket.read # ...?
end

#is_error(str) ⇒ Object

Quick boolean to decide whether the data returned from Erlang was an error.



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# File 'lib/erlang_adapter.rb', line 79

def is_error(str)
  str[0..5] == "Error:"
end

#make_command(erlang_mod, erlang_func, args) ⇒ Object

Create an Erlang command from the ruby-style syntax

erlang_mod

Erlang module

erlang_func

Erlang function

args

Arguments to pass to function. Should be in a Ruby array.



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# File 'lib/erlang_adapter.rb', line 52

def make_command(erlang_mod, erlang_func, args)
  "#{erlang_mod}:#{erlang_func}(#{to_erlang_args(args)})."
end

#to_erlang_args(args) ⇒ Object

Translate a Ruby array to Erlang elements.



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# File 'lib/erlang_adapter.rb', line 57

def to_erlang_args(args)
  args.map{ |x| to_erlang_literal x }.join(',')
end

#to_erlang_literal(x) ⇒ Object

isn’t a basic argument.



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# File 'lib/erlang_adapter.rb', line 64

def to_erlang_literal(x)
  if x.kind_of?(String) then
    "\"#{x}\""
  elsif x.kind_of?(Integer) then
    x
  elsif x.kind_of?(Float) then
    x
  elsif x.kind_of?(Array) then
    "[#{x.map{|y| to_erlang_literal(y)}.join(',')}]"
  else
    raise "Can't use \"#{x.type} Object\" in arguments."
  end
end