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Should I learn C before learning C++? [closed]
...into C++.
I think C++ makes it easy to wrap up all those gotchas (need an array that won't overflow when you use the [] operator and a dodgy index? Sure, make an array class that does bounds checking) but you need to know what they are and get bitten by them before you understand why things are do...
Java 8 Iterable.forEach() vs foreach loop
...e better performance than a traditional for-each loop, at least when using ArrayList and running Hotspot in "-client" mode. While this performance boost is small and negligible for most use cases, there are situations, where this extra performance can make a difference. E.g. library maintainers will...
Samples of Scala and Java code where Scala code looks simpler/has fewer lines?
...public static void main(String[] args) {
List<String> keywords = Arrays.asList("Apple", "Ananas", "Mango", "Banana", "Beer");
Map<Character, List<String>> result = new HashMap<Character, List<String>>();
for(String k : keywords) {
char firstChar =...
What is context in _.each(list, iterator, [context])?
...ameter just sets the value of this in the iterator function.
var someOtherArray = ["name","patrick","d","w"];
_.each([1, 2, 3], function(num) {
// In here, "this" refers to the same Array as "someOtherArray"
alert( this[num] ); // num is the value from the array being iterated
...
Why are exclamation marks used in Ruby methods?
... bangs where a safer alternative exists in the core lib.
For instance, on Array we have .compact and .compact!, both methods mutate the array, but .compact! returns nil instead of self if there are no nil's in the array, which is more surprising than just returning self.
The only non-mutating meth...
Why Choose Struct Over Class?
...initializer, and maintain the intializer...
Basic collection types like Array are structs. The more you use them in your own code, the more you will get used to passing by value as opposed to reference. For instance:
func removeLast(var array:[String]) {
array.removeLast()
println(array) /...
How do you bind an Enum to a DropDownList control in ASP.NET?
...moments).
Better just to iterate through the enum:
Dim itemValues As Array = System.Enum.GetValues(GetType(Response))
Dim itemNames As Array = System.Enum.GetNames(GetType(Response))
For i As Integer = 0 To itemNames.Length - 1
Dim item As New ListItem(itemNames(i), itemValues(i))
dro...
What is reflection and why is it useful?
...ion API to print out every field name and value.
import java.lang.reflect.Array;
import java.lang.reflect.Field;
public static String dump(Object o, int callCount) {
callCount++;
StringBuffer tabs = new StringBuffer();
for (int k = 0; k < callCount; k++) {
tabs.append("\t");...
Ruby Regexp group matching, assign variables on 1 line
...h will return a MatchData object, you can then call #captures to return an Array of captures. Something like this:
#!/usr/bin/env ruby
string = "RyanOnRails: This is a test"
one, two, three = string.match(/(^.*)(:)(.*)/i).captures
p one #=> "RyanOnRails"
p two #=> ":"
p three #=> " T...
iphone Core Data Unresolved error while saving
... what the problem is. The reason for this is because CoreData will put an array of NSError objects in the "top level" NSError object it returns if there is more than one problem (This is why you see error 1560, which indicates multiple problems, and an array of error 1570s). It appears that CoreDa...