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Understanding repr( ) function in Python
...>>> x
'foo'
So the name x is attached to 'foo' string. When you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the ...
What's the difference between the build and create methods in FactoryGirl?
...g FactoryGirl.build(:factory_name) does not persist to the db and does not call save!, so your Active Record validations will not run. This is much faster, but validations might be important.
Using FactoryGirl.create(:factory_name) will persist to the db and will call Active Record validations. Thi...
Factors in R: more than an annoyance?
... of the basic data types in R is factors. In my experience factors are basically a pain and I never use them. I always convert to characters. I feel oddly like I'm missing something.
...
Xcode changes unmodified storyboard and XIB files
...cument based on the logical tree structure, clears the storyboard file and calls XMLDataWithOptions: to fill the file again. Because sets do not preserve the order of their elements, even the slightest modification could change the whole storyboard XML file.
Why does the class tag disappear or reapp...
What is the difference between the Data Mapper, Table Data Gateway (Gateway), Data Access Object (DA
...e same thing - encapsulate the database logic for a specific entity so the calling code has no knowledge of the underlying persistence layer. From my brief research all of them typically implement your standard CRUD methods and abstract away the database-specific details.
...
Why is Python 3.x's super() magic?
In Python 3.x, super() can be called without arguments:
1 Answer
1
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Creating instance of type without default constructor in C# using reflection
...FormatterServices.GetUninitializedObject() will create an instance without calling a constructor. I found this class by using Reflector and digging through some of the core .Net serialization classes.
I tested it using the sample code below and it looks like it works great:
using System;
using ...
Insert picture/table in R Markdown [closed]
... HOWTOs for tables and images. Top on my list are:
Pandoc readme, specifically tables
RStudio's RMarkdown, more details in basics (including tables) and a rewrite of pandoc's markdown.
Pictures are very simple to use but do not offer the ability to adjust the image to fit the page (see Update, b...
Can I make a function available in every controller in angular?
If I have a utility function foo that I want to be able to call from anywhere inside of my ng-app declaration. Is there someway I can make it globally accessible in my module setup or do I need to add it to the scope in every controller?
...
Is Chrome's JavaScript console lazy about evaluating arrays?
...s loaded), even when the console is open, whenever the page is refreshed. Calling console.log when the console is not yet active only results in a reference to the object being queued, not the output the console will contain. Therefore, the array (or any object), will not be evaluated until the co...