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Check if a table exists in Rails
...iveRecord::Base.connection.data_source_exists? 'table_name' is the correct one now
– Dorian
Dec 30 '16 at 1:35
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What's the difference between tilde(~) and caret(^) in package.json?
...4 to <3.0.0.
See Comments below for exceptions, in particular for pre-one versions, such as ^0.2.3
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How do I call Objective-C code from Swift?
In Swift, how does one call Objective-C code?
17 Answers
17
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What is the difference between Cygwin and MinGW?
...andard Unix environment and uses Unix-specific features such as those mentioned earlier. By default, code compiled in MinGW's GCC will compile to a native Windows X86 target, including .exe and .dll files, though you could also cross-compile with the right settings, since you are basically using th...
How to split strings across multiple lines in CMake?
...at I do not know how to split a simple string into multiple lines to avoid one huge line. Consider this basic code:
7 Answe...
How do I move the turtle in LOGO? [closed]
...issuing commands in the correct syntax. E.G.:
forward 100
There is only one necessary command to move the turtle. It is forward which has the mnemonic fd. When working with a robot (real) turtle as opposed to a graphics based (virtual) one, you might find that the turning commands left and right ...
What does $$ (dollar dollar or double dollar) mean in PHP?
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The inner $ resolves the a variable to a string, and the outer one resolves a variable by that string.
So, consider this example
$inner = "foo";
$outer = "inner";
The variable:
$$outer
would equal the string "foo"
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Checking if a string can be converted to float in Python
...ular expression:
import re
if re.match(r'^-?\d+(?:\.\d+)?$', element) is None:
print "Not float"
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ASP.NET MVC - Set custom IIdentity or IPrincipal
...l.asax.cs - Reading cookie and replacing HttpContext.User object, this is done by overriding PostAuthenticateRequest
protected void Application_PostAuthenticateRequest(Object sender, EventArgs e)
{
HttpCookie authCookie = Request.Cookies[FormsAuthentication.FormsCookieName];
if (authCookie...
Is there an upside down caret character?
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A powerful option – and one which also boosts creativity – is designing your own characters using box drawing characters.
Want a down pointing "caret"? Here's one: ╲╱
I've recently discovered them — and I take great pleasure at using such ...