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Difference between var_dump,var_export & print_r
What is the difference between var_dump , var_export and print_r ?
2 Answers
2
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How do I implement an Objective-C singleton that is compatible with ARC?
...redInstance
{
static MyClass *sharedInstance = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
sharedInstance = [[MyClass alloc] init];
// Do any other initialisation stuff here
});
return sharedInstance;
}
...
Swift - How to convert String to Double
...ormatter()
formatter.locale = Locale.current // USA: Locale(identifier: "en_US")
formatter.numberStyle = .decimal
let number = formatter.number(from: "9,999.99")
Currency formats
let usLocale = Locale(identifier: "en_US")
let frenchLocale = Locale(identifier: "fr_FR")
let germanLocale = Locale(id...
How SID is different from Service name in Oracle tnsnames.ora
...e as SID
and you can also give it any other
name you want.
SERVICE_NAME is the new feature from
oracle 8i onwards in which database
can register itself with listener. If
database is registered with listener
in this way then you can use
SERVICE_NAME parameter in tnsnames.ora
othe...
Why should the copy constructor accept its parameter by reference in C++?
...dited Jun 21 '12 at 8:10
someone_ smiley
90411 gold badge2121 silver badges3838 bronze badges
answered Apr 21 '10 at 19:14
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How can I switch my git repository to a particular commit
...anch (locally):
With the commit hash (or part of it)
git checkout -b new_branch 6e559cb
or to go back 4 commits from HEAD
git checkout -b new_branch HEAD~4
Once your new branch is created (locally), you might want to replicate this change on a remote of the same name: How can I push my chang...
Is there a performance gain in using single quotes vs double quotes in ruby?
...
$ ruby -v
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin11.0.0]
$ cat benchmark_quotes.rb
# As of Ruby 1.9 Benchmark must be required
require 'benchmark'
n = 1000000
Benchmark.bm(15) do |x|
x.report("assign single") { n.times do; c = 'a string'; end}
x.report("assi...
Add a CSS class to
...
<%= f.submit 'name of button here', :class => 'submit_class_name_here' %>
This should do. If you're getting an error, chances are that you're not supplying the name.
Alternatively, you can style the button without a class:
form#form_id_here input[type=submit]
Try that,...
Twitter image encoding challenge [closed]
...3, 10, 11, 1000, 1000. I also commented out the first definition of number_assigned and codes, and uncommented out the last definitions of them to select the CJK Unified character set.
share
...
Set a default parameter value for a JavaScript function
...S2015, default parameters are in the language specification.
function read_file(file, delete_after = false) {
// Code
}
just works.
Reference: Default Parameters - MDN
Default function parameters allow formal parameters to be initialized with default values if no value or undefined is pass...