Ruby detect if a column value has changed [closed] - ruby

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So I have this line:
if self.company_changed?
And it works fine but this detects if the company has changed on the object. I need to know if the database value has changed and not if the value in memory has changed. So I tried this:
if :company_changed?
This seems to work in debug mode when I only execute the one line. If I let it run, it fails in testing on an infinite loop.
My question is what can be used in ruby to check to see if the column value has actually changed.

I'm pretty sure you're actually talking about ActiveRecord. In which case, you'd need to re-fetch the record to see if the value has changed in the database.
self.class.find(self.id).company != self.company
A general purpose method for this might be something like:
def attr_changed_in_db?(attr)
self.class.find(self.id).attributes[attr] != self.attributes[attr]
end

There is an excellent screencast on this by the great Ryan Bates.

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Ruby on Rails The kept [closed]

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od_practice.partnerships.kept.first&.omd_practice&.id
I have seen people use the word kept.first to pull data from database in ruby on rail . What does these words mean ? i have tried to do some research and i seem not find any solution. Can someone explain me please ?
This is called a message send in Ruby. In some other languages, it might be called a method call.
It is sending the message kept with no arguments to the object that was the result of evaluating the beginning of the message chain. This message send will in turn result in an object being returned, and it is then sending the message first to that object, again with no arguments.

What is ctx and arg in discord.py? [closed]

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So I have been learning discord.py and keep getting stuck in the same part. I don't know what ctx and arg mean. I can't find much in their documentation. I've seen it like ctx.send or async def blank(ctx). What does it do and what use cases would it be used for?
ctx is short for context. It is used by discord.ext.commands and includes information like who executed the command, where it was executed and so on. ctx.send() is basically a helper function which makes your life easier. You can read its description in the docs to find out how it works and what it does. You just need to read it.
arg is short for argument. It is usually used as a variable length argument list.

How to write a file in ruby without a terminating newline [closed]

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For debugging purposes, I want to alter a rake test so as not to end a saved file with a newline.
I don't know ruby. How do I do this? (file.print doesn't seem to work.)
Not clear what you are doing, but since you tried file.print, it looks like you have access to what is to be printed. Let's say this is string. My guess is that string already has a newline character. Then do:
file.print(string.chomp)

Storing the object of Select_list [closed]

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Please consider the below code
a=b.select_lists[0]
a.select("Agent")
In the aforementioned code, the first line is taking so much time, So Can anyone tell me Is there any way to store value of "a" object for further use without getting from b.select_lists[0]? Or Is there anyway can we directly get the value of 'a'?
The code which I am trying to write for the select list follows below
<select class="ng-valid ng-dirty" style="" ng-change="selectionsAgentType(AgentType)" ng-model="AgentType"> <select class="ng-valid ng-dirty" ng-change="AgentCategorySelected(agentoptions)" ng-model="agentoptions">
If option with text: 'Agent' is unique on this page.
If you need just simulate select
b.option(:text, 'Agent').select
Also, if you need value of this option
a = b.option(:text, 'Agent').value
Else,
b.select_lists.first.option(:text, 'Agent').select
a = b.select_lists.first.option(:text, 'Agent').value

Retrieving people who +1 an URL [closed]

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I've burning out the past 2 days trying to come with a recipe to get all the People who have +1 an URL, I'm trying to calculate the potential reach of a publication in Google+.
I did get the public shares of a URL using Ripple, amount and users, but is not the same.
I writing my app in ruby, but at this moment, I can't care less about the language.
To get clear view of my problem, please read my comment below.
There is no API method to get a list of who as +1'd a URL. If you would like to see such a feature please open a new issue.

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