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Read only the first line of a file?
...od (Python 2 docs, Python 3 docs):
with open('myfile.txt') as f:
first_line = f.readline()
Some notes:
As noted in the docs, unless it is the only line in the file, the string returned from f.readline() will contain a trailing newline. You may wish to use f.readline().strip() instead to rem...
How is pattern matching in Scala implemented at the bytecode level?
...atterns like or patterns and combinations like "case Foo(45, x)", but generally those are just logical extensions of what I just described. Patterns can also have guards, which are additional constraints on the predicates. There are also cases where the compiler can optimize pattern matching, e.g...
Multiple DB Contexts in the Same DB and Application in EF 6 and Code First Migrations
...lied to the target database.
Applying explicit migrations: [201402032113124_InitialDatabaseCreation].
Applying explicit migration: 201402032113124_InitialDatabaseCreation.
Running Seed method.
PM> Update-Database -ConfigurationTypeName WebApplication3.Migrations.AnotherDbContext.Configuration
Sp...
Swift - Convert to absolute value
...alue.magnitude) // prints: 5
#2. Get absolute value of an Int from abs(_:) method
Swift has a global numeric function called abs(_:) method. abs(_:) has the following declaration:
func abs<T>(_ x: T) -> T where T : Comparable, T : SignedNumeric
Returns the absolute value of the g...
How to add “active” class to Html.ActionLink in ASP.NET MVC
...ges, it would be smart to have a way to apply that selected class automatically based on the current page rather than copy the menu multiple times and do it manually.
The easiest way is to simply use the values contained in ViewContext.RouteData, namely the Action and Controller values. We could b...
What makes Lisp macros so special?
... nil)
;; loop from 0 upto and including 9
(loop for x in (range 10)
;; test for divisibility by two
if (= (mod x 2) 0)
;; append to the list
do (setq divisibleByTwo (append divisibleByTwo (list x))))
Before I go further, I should better explain what a macro is. It is a transformati...
Character reading from file in Python
...iles in update mode, allowing both reading and writing:
with codecs.open('test', encoding='utf-8', mode='w+') as f:
f.write(u'\u4500 blah blah blah\n')
f.seek(0)
print repr(f.readline()[:1])
EDIT: I'm assuming that your intended goal is just to be able to read the file properly into a...
Which @NotNull Java annotation should I use?
... with each others' @NotNull / @NonNull / @Nonnull annotation and listing all of them in my code would be terrible to read. Any suggestions of which one is the 'best'? Here is the list of equivalent annotations I've found:
...
Download a file by jQuery.Ajax
...ence is when a file download occurs.
I created jQuery File Download which allows for an "Ajax like" experience with file downloads complete with OnSuccess and OnFailure callbacks to provide for a better user experience. Take a look at my blog post on the common problem that the plugin solves and so...
Unable to create Android Virtual Device
...
Simply because CPU/ABI says "No system images installed for this target". You need to install system images.
In the Android SDK Manager check that you have installed "ARM EABI v7a System Image" (for each Android version from 4.0 and on you have to install a system image to ...