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What is the difference between parseInt() and Number()?
...are semantically different, the Number constructor called as a function performs type conversion and parseInt performs parsing, e.g.:
// parsing:
parseInt("20px"); // 20
parseInt("10100", 2); // 20
parseInt("2e1"); // 2
// type conversion
Number("20px"); // NaN
Number("2e1"); ...
How to convert an Stream into a byte[] in C#? [duplicate]
...nd later, the Stream class has a built-in CopyTo method that you can use.
For earlier versions of the framework, the handy helper function to have is:
public static void CopyStream(Stream input, Stream output)
{
byte[] b = new byte[32768];
int r;
while ((r = input.Read(b, 0, b.Length))...
Create an enum with string values
...you can use string literal types to provide a reliable and safe experience for named string values (which is partially what enums are used for).
type Options = "hello" | "world";
var foo: Options;
foo = "hello"; // Okay
foo = "asdf"; // Error!
More : https://www.typescriptlang.org/docs/handbook...
How to write LaTeX in IPython Notebook?
...ave a %%latex magic that makes the whole cell Latex without the $$ wrapper for each line.
Refer notebook tour for Rich Display System
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Rails 4: how to use $(document).ready() with turbo-links
...ument).ready(ready)
$(document).on('page:load', ready)
last line listens for page load which is what turbo links will trigger.
Edit...adding Javascript version (per request):
var ready;
ready = function() {
...your javascript goes here...
};
$(document).ready(ready);
$(document).on('page:lo...
Get Visual Studio to run a T4 Template on every build
...ild event every time you add a new .tt file to the project.
add TextTransform.exe to your %PATH%
created a batch file named transform_all.bat (see below)
create a pre-build event "transform_all ..\.."
transform_all.bat
@echo off
SETLOCAL ENABLEDELAYEDEXPANSION
:: set the working dir (default t...
Uncaught SyntaxError: Unexpected token :
...php redirect that is causing this in Chrome.
– Works for a Living
Mar 8 '16 at 20:20
7
To add to ...
Can't find the 'libpq-fe.h header when trying to install pg gem
.../postgresql/libpq-fe.h
...
So try installing libpq-dev or its equivalent for your OS:
For Ubuntu/Debian systems: sudo apt-get install libpq-dev
On Red Hat Linux (RHEL) systems: yum install postgresql-devel
For Mac Homebrew: brew install postgresql
For Mac MacPorts PostgreSQL: gem install pg -- -...
Abort makefile if variable not set
...re going to test many variables, it's worth defining an auxiliary function for that:
# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
# 1. Variable name(s) to test.
# 2. (optional) Error message to print.
check_defined = \
$(stri...
When is null or undefined used in JavaScript? [duplicate]
... to does not exist.
This is one of the few times you may not want to test for equality-
if(x!==undefined) will be true for a null value
but if(x!= undefined) will be true (only) for values that are not either undefined or null.
...