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int* foo(int bar) { int baz = 6; baz += bar; return &baz; /* (&baz) copied to new memory location outside of foo. */ } /* (1) The lifetime of baz and bar end here as they have automatic storage * duration (local variables), thus the returned pointer is not valid! */ ...

Starting with a given list a: a = [1, 2, 3, 4, 5] append(value) – appends a new element to the end of the list. # Append values 6, 7, and 7 to the list a.append(6) a.append(7) a.append(7) # a: [1, 2, 3, 4, 5, 6, 7, 7] # Append another list b = [8, 9] a.append(b) # a: [1, 2, 3, 4, ...

int x = 0; int y = 5 / x; /* integer division */ or double x = 0.0; double y = 5.0 / x; /* floating point division */ or int x = 0; int y = 5 % x; /* modulo operation */ For the second line in each example, where the value of the second operand (x) is zero, the behaviour is undefine...

Let's say we have two classes, Cat and Dog. class Cat def eat die unless has_food? self.food_amount -= 1 self.hungry = false end def sound puts "Meow" end end class Dog def eat die unless has_food? self.food_amount -= 1 self.hungry = f...

Let's say you want to generate counts or subtotals for a given value in a column. Given this table, "Westerosians": NameGreatHouseAllegienceAryaStarkCerceiLannisterMyrcellaLannisterYaraGreyjoyCatelynStarkSansaStark Without GROUP BY, COUNT will simply return a total number of rows: SELE...

fetch('/example.json', { headers: new Headers({ 'Accept': 'text/plain', 'X-Your-Custom-Header': 'example value' }) });

Special characters (like the character class brackets [ and ] below) are not matched literally: match = re.search(r'[b]', 'a[b]c') match.group() # Out: 'b' By escaping the special characters, they can be matched literally: match = re.search(r'\[b\]', 'a[b]c') match.group() # Out: '[b]' T...

' Omitting the 4th and 5th argument ("xpos" and "ypos") will result in the prompt ' being display center of the parent screen exampleString = InputBox("What is your name?", "Name Check", "Jon Skeet", 2500, 2000) WScript.Echo "Your name ...

iOS 8 In order to present local notifications to the user, you have to register your app with the device: Swift let settings = UIUserNotificationSettings(forTypes: [.Badge, .Sound, .Alert], categories: nil) UIApplication.sharedApplication().registerUserNotificationSettings(settings) Objective...

Steam has a games under $10 section of their store page. Somewhere deep in the heart of their systems, there's probably a query that looks something like: SELECT * FROM Items WHERE Price < 10

The Basics The simplist way to convert one date format into another is to use strtotime() with date(). strtotime() will convert the date into a Unix Timestamp. That Unix Timestamp can then be passed to date() to convert it to the new format. $timestamp = strtotime('2008-07-01T22:35:17.02'); $new_...

re.findall(r"[0-9]{2,3}", "some 1 text 12 is 945 here 4445588899") # Out: ['12', '945', '444', '558', '889'] Note that the r before "[0-9]{2,3}" tells python to interpret the string as-is; as a "raw" string. You could also use re.finditer() which works in...

4.0 To uppercase $ v="hello" # Just the first character $ printf '%s\n' "${v^}" Hello # All characters $ printf '%s\n' "${v^^}" HELLO # Alternative $ v="hello world" $ declare -u string="$v" $ echo "$string" HELLO WORLD To l...

Number('0') === 0 Number('0') will convert the string ('0') into a number (0) A shorter, but less clear, form: +'0' === 0 The unary + operator does nothing to numbers, but converts anything else to a number. Interestingly, +(-12) === -12. parseInt('0', 10) === 0 parseInt('0', 10) will c...

String(0) === '0' String(0) will convert the number (0) into a string ('0'). A shorter, but less clear, form: '' + 0 === '0'

The Problem The abstract equality and inequality operators (== and !=) convert their operands if the operand types do not match. This type coercion is a common source of confusion about the results of these operators, in particular, these operators aren't always transitive as one would expect. &...

The @property decorator can be used to define methods in a class which act like attributes. One example where this can be useful is when exposing information which may require an initial (expensive) lookup and simple retrieval thereafter. Given some module foobar.py: class Foo(object): def __...

InterruptedException is a confusing beast - it shows up in seemingly innocuous methods like Thread.sleep(), but handling it incorrectly leads to hard-to-manage code that behaves poorly in concurrent environments. At its most basic, if an InterruptedException is caught it means someone, somewhere, c...

If you want to use @property to implement custom behavior for setting and getting, use this pattern: class Cash(object): def __init__(self, value): self.value = value @property def formatted(self): return '${:.2f}'.format(self.value) @formatted.setter def ...

SELECT your_columns, COUNT(*) OVER() as Ttl_Rows FROM your_data_set idnameTtl_Rows1example52foo53bar54baz55quux5 Instead of using two queries to get a count then the line, you can use an aggregate as a window function and use the full result set as the window. This can be used as a base for fur...