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Output can be restricted by specifying line ranges as git blame -L <start>,<end> Where <start> and <end> can be: line number git blame -L 10,30 /regex/ git blame -L /void main/, git blame -L 46,/void foo/ +offset, -offset (only for <end>) git blame -...

One of the uses of recursion is to navigate through a hierarchical data structure, like a file system directory tree, without knowing how many levels the tree has or the number of objects on each level. In this example, you will see how to use recursion on a directory tree to find all sub-directorie...

It is a good idea to maintain a web-scraping session to persist the cookies and other parameters. Additionally, it can result into a performance improvement because requests.Session reuses the underlying TCP connection to a host: import requests with requests.Session() as session: # all req...

Because LINQ uses deferred execution, we can have a query object that doesn't actually contain the values, but will return the values when evaluated. We can thus dynamically build the query based on our control flow, and evaluate it once we are finished: IEnumerable<VehicleModel> BuildQuery(i...

While RODBC is restricted to Windows computers with compatible architecture between R and any target RDMS, one of its key flexibilities is to work with Excel files as if they were SQL databases. require(RODBC) con = odbcConnectExcel("myfile.xlsx") # open a connection to the Excel file s...

First need to create a final static logger object: final static Logger logger = Logger.getLogger(classname.class); Then, call logging methods: //logs an error message logger.info("Information about some param: " + parameter); // Note that this line could throw a NullPointerException!...

Log4j gives you posibility to log data into console and file at same time. Create a log4j.properties file and put inside this basic configuration: # Root logger option log4j.rootLogger=DEBUG, stdout, file # Redirect log messages to console log4j.appender.stdout=org.apache.log4j.ConsoleAppende...

If the help function is called in the console without any arguments, Python presents an interactive help console, where you can find out about Python modules, symbols, keywords and more. >>> help() Welcome to Python 3.4's help utility! If this is your first time using Python, you sho...

To get the value of the last result from your last expression in the console, use an underscore _. >>> 2 + 2 4 >>> _ 4 >>> _ + 6 10 This magic underscore value is only updated when using a python expression that results in a value. Defining functions or for loops ...

The console for the primary version of Python can usually be opened by typing py into your windows console or python on other platforms. $ py Python 3.4.3 (v3.4.3:9b73f1c3e601, Feb 24 2015, 22:44:40) [MSC v.1600 64 bit (AMD64)] on win32 Type "help", "copyright", "credits&...

Python has a variety of command-line switches which can be passed to py. These can be found by performing py --help, which gives this output on Python 3.4: Python Launcher usage: py [ launcher-arguments ] [ python-arguments ] script [ script-arguments ] Launcher arguments: -2 : Launch ...

The Python console adds a new function, help, which can be used to get information about a function or object. For a function, help prints its signature (arguments) and its docstring, if the function has one. >>> help(print) Help on built-in function print in module builtins: print(.....

A simple static file server would look like this: package main import ( "net/http" ) func main() { muxer := http.NewServeMux() fileServerCss := http.FileServer(http.Dir("src/css")) fileServerJs := http.FileServer(http.Dir("src/js")) file...

Install the SDK Download & unzip the SDK Make sure you are using the latest version of Xcode (7.0+) and targeting iOS 7.0 or highe Download SDK Add the SDKs to your app Drag the Parse.framework and Bolts.framework you downloaded into your Xcode project folder target. Make sure th...

Sometimes you need to keep a linear (non-branching) history of your code commits. If you are working on a branch for a while, this can be tricky if you have to do a regular git pull since that will record a merge with upstream. [alias] up = pull --rebase This will update with your upstream so...

You can use the star * when writing a function to collect all positional (ie. unnamed) arguments in a tuple: def print_args(farg, *args): print("formal arg: %s" % farg) for arg in args: print("another positional arg: %s" % arg) Calling method: print_args(1, &...

You can define a function that takes an arbitrary number of keyword (named) arguments by using the double star ** before a parameter name: def print_kwargs(**kwargs): print(kwargs) When calling the method, Python will construct a dictionary of all keyword arguments and make it available in ...

A common use case for *args in a function definition is to delegate processing to either a wrapped or inherited function. A typical example might be in a class's __init__ method class A(object): def __init__(self, b, c): self.y = b self.z = c class B(A): def __init__(...

You can use a dictionary to assign values to the function's parameters; using parameters name as keys in the dictionary and the value of these arguments bound to each key: def test_func(arg1, arg2, arg3): # Usual function with three arguments print("arg1: %s" % arg1) print("a...

Detailed instructions on getting facebook set up or installed.