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Using boolean values in C
...e 1
#define false 0
Explanation
Option 1 will work only if you use C99 and it's the "standard way" to do it. Choose this if possible.
Options 2, 3 and 4 will have in practice the same identical behavior. #2 and #3 don't use #defines though, which in my opinion is better.
If you are undecided, ...
Invoking JavaScript code in an iframe from the parent page
Basically, I have an iframe embedded in a page and the iframe has some JavaScript routines I need to invoke from the parent page.
...
How to declare variable and use it in the same Oracle SQL script?
I want to write reusable code and need to declare some variables at the beginning and reuse them in the script, such as:
10...
how to change default python version?
... in my mac. After I run /Applications/Python 3.2/Update Shell Profile.command , it's confusing that when I type python -V in Terminal it says that Python 2.6.1 , how can I change the default python version?
...
Retrieving the last record in each group - MySQL
...dowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1...
IntelliJ inspection gives “Cannot resolve symbol” but still compiles code
...
First of all you should try File | Invalidate Caches and if it doesn't help, delete IDEA system directory. Then re-import the Maven project and see if it helps.
In some weird cases compiled classes may report wrong info and confuse IDEA. Verify that the classes from this jar r...
Split code over multiple lines in an R script
... issue, try
R> setwd(paste("~/a/very/long/path/here",
"/and/then/some/more",
"/and/then/some/more",
"/and/then/some/more", sep=""))
which also illustrates that it is perfectly fine to break code across multiple lines.
...
What is the difference between static func and class func in Swift?
...
Is it simply that static is for static functions of structs and enums, and class for classes and protocols?
That's the main difference. Some other differences are that class functions are dynamically dispatched and can be overridden by subclasses.
Protocols use the class keyword, b...
Basic HTTP authentication with Node and Express 4
...n: 'yourlogin', password: 'yourpassword'} // change this
// parse login and password from headers
const b64auth = (req.headers.authorization || '').split(' ')[1] || ''
const [login, password] = Buffer.from(b64auth, 'base64').toString().split(':')
// Verify login and password are set and co...
mysql Foreign key constraint is incorrectly formed error
I have two tables, table1 is the parent table with a column ID and table2 with a column IDFromTable1 (not the actual name) when I put a FK on IDFromTable1 to ID in table1 I get the error Foreign key constraint is incorrectly formed error . I would like to delete table 2 record if tab...