Could anyone advise me what is wrong on this script? I am a complete beginner with ruby, but I still do not understand why this object is empty in the dump. Thank you for your advice.
require 'sinatra'
class Person
def initialize(first_name, last_name, age, country)
#per_first_name = first_name
#per_last_name = last_name
#per_age = age
#per_country = country
end
def get_basic_info()
puts Array.[](#per_first_name, #per_last_name, #per_age, #per_country)
end
end
get '/basicInfo' do
xavier = Person.new('Tada', 'Bada', 25, 'CR')
xavier.inspect
end
It doesn't seem to be an error, i think you are getting a # in your page when going to http://localhost:4567/basicInfo, and that's the expected behavior since your are calling inspect on your new created Person object.
I assume that you want to display get_basic_info instead, if so, you need to do a couple of changes:
First, remove puts from get_basic_info since puts will print in console, not on your page:
def get_basic_info()
Array.[](#per_first_name, #per_last_name, #per_age, #per_country)
end
Second, call your method before calling inspect, so you get the array of basic info before inspecting it:
get '/basicInfo' do
xavier = Person.new('Tada', 'Bada', 25, 'CR')
xavier.get_basic_info.inspect
end
Related
I have a lab through school where I need to create a form that takes in basketball team attributes, team name, coach, point guard etc., and want to know if there is any way to dynamically create instance variables and symbols using an iterator of sorts instead of hard coding them?
Here is the hard-coded version of what I mean:
post "/team" do
#name = params["name"]
#coach = params["coach"]
#pg = params["pg"]
#sg = params["sg"]
#pf = params["pf"]
#sf = params["sf"]
#c = params["c"]
erb :team
end
I want to use something similar to this:
post '/team' do
params.each do |parameter|
#[parameter] = params["#{parameter}"]
end
erb :team
end
When I run the above code I receive a unexpected end-of-input syntax error.
Try to use instance_variable_set,
something like this:
post '/team' do
params.each do |key, value|
self.instance_variable_set("##{key}", value)
end
erb :team
end
I was working on coding challenge called Robot name. I also had tests for that. The program passed all the tests. The code is below..
class Robot
attr_accessor :name
##robots = []
def initialize
#name = self.random_name
##robots << self.name
end
def random_name
name = ''
2.times do
name << ('a'..'z').to_a.sample
end
3.times do
name << (1..9).to_a.sample.to_s
end
no_duplicate(name.upcase)
end
def reset
#name = self.random_name
end
def no_duplicate(name)
if ##robots.include? name
reset
else
name
end
end
end
If you need to see the tests file you can look it up here robot_name_tests.
Then I started to refactor and one of the first things was to refactor no_duplicate method. So after refactoring the code looked like this
class Robot
...
# the rest of code stayed the same
def no_duplicate(name)
##robots.include? name ? reset : name
end
end
With this version all tests showed SystemStackError: stack level too deep. Why does it give this error and what is going on behind the scenes in both cases considering the code provided? Thanks!
I like your poetry mode code but it has led you into trouble here.
One way to kinda keep it in poetry mode but fix your operator priority issue is to do this:
def no_duplicate(name)
(##robots.include? name) ? reset : name
end
Update: if you work in Big Corporation With Coding Standards you will need to make it a bit more boring. I thought this was obvious but the gallery is correctly noting the usual solution:
##robots.include?(name) ? reset : name
Hi I made it to the lase exercise os Learn Ruby The Hard Way, and I come at the wall...
Here is the test code:
def test_gothon_map()
assert_equal(START.go('shoot!'), generic_death)
assert_equal(START.go('dodge!'), generic_death)
room = START.go("tell a joke")
assert_equal(room, laser_weapon_armory)
end
And here is the code of the file it should test:
class Room
attr_accessor :name, :description, :paths
def initialize(name, description)
#name = name
#description = description
#paths = {}
end
def ==(other)
self.name==other.name&&self.description==other.description&&self.paths==other.paths
end
def go(direction)
#paths[direction]
end
def add_paths(paths)
#paths.update(paths)
end
end
generic_death = Room.new("death", "You died.")
And when I try to launch the test file I get an error:
generic_death = Room.new("death", "You died.")
I tried to set the "generic_death = Room.new("death", "You died.")" in test_gothon_map method and it worked but the problem is that description of the next object is extremely long, so my questions are:
why assertion doesn't not respond to defined object?
can it be done different way then by putting whole object to testing method, since description of the next object is extremely long...
The nature of local variable is that they are, well, local. This means that they are not available outside the scope they were defined.
That's why ruby does not know what generic_death means in your test.
You can solve this in a couple of ways:
define rooms as constants in the Room class:
class Room
# ...
GENERIC_DEATH = Room.new("death", "You died.")
LASER_WEAPON_ARMORY = Room.new(...)
end
def test_gothon_map()
assert_equal(Room::START.go('shoot!'), Room::GENERIC_DEATH)
assert_equal(Room::START.go('dodge!'), Room::GENERIC_DEATH)
room = Room::START.go("tell a joke")
assert_equal(room, Room::LASER_WEAPON_ARMORY)
end
assert the room by its name, or some other identifier:
def test_gothon_map()
assert_equal(START.go('shoot!').name, "death")
assert_equal(START.go('dodge!').name, "death")
room = START.go("tell a joke")
assert_equal(room.name, "laser weapon armory")
end
I'm writing a wrapper for an XML API using Nokogiri to build the XML for submission.
In order to keep my code DRY, I'm using custom blocks for the first time and just getting to grips with how to pass variables back and forth and how that works.
What I'm doing at the moment is this:
# Generic action
def action(xml, action_title, test=false)
xml.request do
xml.login do
xml.username("my_user")
xml.password("my_pass")
end
xml.action(action_title)
xml.params do
yield
end
end
end
# Specific action
def get_users(city = "", gender = "")
build = Nokogiri::XML::Builder.new do |xml|
action(xml, "getusers") do
xml.city(city) unless city.blank?
xml.gender(gender) unless gender.blank?
end
end
do_stuff_to(build)
end
Ideally, I'd like to the specific action method to look like this:
def get_users(city = "", gender = "")
action("getusers") do |xml|
xml.city(city) unless city.blank?
xml.gender(gender) unless gender.blank?
end
end
In doing so, I'd want the other logic currently in the specific action method to be moved to the generic action method with the generic action method returning the results of do_stuff_to(build).
What I'm struggling with is how to pass the xml object from action() back to get_users(). What should action() look like in order to achieve this?
Turns out this was quite simple. The action method needs to be changed so it looks like this:
def action(action_title)
build = Nokogiri::XML::Builder.new do |xml|
xml.request do
xml.login do
xml.username("my_user")
xml.password("my_pass")
end
xml.action(action_title)
xml.params do
yield xml
end
end
end
do_stuff_to(build)
end
That meant the specific action method could be called like this to the same effect:
def get_users(city = "", gender = "")
action("getusers") do |xml|
xml.city(city) unless city.blank?
xml.gender(gender) unless gender.blank?
end
end
I have a YAML file books.yaml:
- !ruby.object:Book
title: Ruby for Newbz
author: LeeRoy Jenkins
category: Educational
I already have a method that adds books to this file, but I need a method that can search the YAML file using a regular expression. If no book matches the title then it should raise an exception NoBookfound. If there are any matches, that list should be returned to the caller.
Here is my existing code:
require 'yaml'
require './book'
class Library
attr_accessor :books
def initialize file_name = false
#books = file_name ? YAML::load(File.read(file_name)) : []
end
def add_book(book)
#books.push(book)
end
def search_library(file_name , book)
if
YAML::load(File.read(file_name)).include?(book) == false
raise 'No Book Found'
end
end
end
This is something I tried for the exception portion, but I feel like I'm way off. I'm really new to Ruby and this seems to be a pretty hard task. Does anyone have any ideas?
What you need is to test the class from the loaded object:
book = YAML::load(File.read(file_name))
raise 'No Book Found' unless book.kind_of? Book
There are also some kind_of? alternatives, which you can read about the differences on this nice question
Based on your post, I guess that book param is a Regexp object.
I think you should remove the file_name param from search method, since the file is already loaded on initialize method.
My implemetation would be:
def search_library term
#books.find_all {|b| b.title =~ term}
end
Since you already have "#books" in an enumerable you can use the select method to find books whose title have the search term as a substring.
def search_library(term)
matches = #books.select { |x| x.title.index(term) }
raise "No books have title like '#{term}'" if matches.empty?
matches
end