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How to check if a model has a certain column/attribute?
...tring name of your attribute.
In this case: Number.column_names.include? 'one'
For an instance
Use record.has_attribute?(:attr_name) or record.has_attribute?('attr_name') (Rails 3.2+) or record.attributes.has_key? attr_name.
In this case: number.has_attribute?(:one) or number.has_attribute?('one...
adb server version doesn't match this client
...wer. It started after updating android studio. I was going crazy with this one, reinstalled the sdk and everything. I thought it was a bug in the new version.
– TacoEater
Dec 24 '14 at 20:19
...
setTimeout in for-loop does not print consecutive values [duplicate]
... in the OP and in my answer, and the time delay value is the same for each one, then once that amount of time has elapsed all the timer handlers will be called one after another in rapid succession.
If what you need is for the handlers to be called at intervals, you can either use setInterval(), wh...
Git branch strategy for small dev team [closed]
... of code, where code in a less stable branch will eventually "graduate" to one considered more stable after testing and general approval by your team.
Step by step, your workflow under this model might look like this:
You need to fix a bug.
Create a branch called myfix that is based on the develo...
Swift and mutating struct
...two separated classes for each concept, but in Swift, you can do this with one struct. Half work.
For C/C++ programmers, this is also very familiar concept. This is exactly what const keyword do in C/C++.
Also, immutable value can be very nicely optimised. In theory, Swift compiler (or LLVM) can p...
How to implement a queue with three stacks?
... this link: http://www.eecs.usma.edu/webs/people/okasaki/jfp95/index.html
One of them is O(1) with three stacks BUT it uses lazy execution, which in practice creates extra intermediate data structures (closures).
Another of them is O(1) but uses SIX stacks. However, it works without lazy execution...
Multiple GitHub Accounts & SSH Config
... needed to make to get this to work. In trying to get two profiles set up, one for personal and one for work, my ~/.ssh/config was roughly as follows:
Host me.github.com
HostName github.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/me_rsa
Host work.github.com
HostName ...
nonlocal keyword in Python 2.x
... but it seems like this keyword is not available in python 2.x. How should one access nonlocal variables in closures in these versions of python?
...
What does the Reflect object do in JavaScript?
...iding the need for a global Proxy binding.
Most methods in this module map one-to-one onto Proxy traps. Proxy handlers need these methods to conveniently forward operations, as shown below.
So, the Reflect object provides a number of utility functions, many of which appear to overlap with ES5 me...
What is
...
It means that T must implement Comparable<T itself or one of T's superclasses>
The sense is that because SortedList is sorted, it must know how to compare two classes of its generics T parameter. That's why T must implement Comparable<T itself or one of T's superclasses>...