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How to get a Docker container's IP address from the host
...n. Maybe provide two examples clearly labelled Linux and Windows. I literally just typed the example, checked the docs which also uses single quotes and then Googled the error. I'm sure I'm not alone.
– Wyck
Apr 15 '19 at 18:42
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PHP session lost after redirect
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First, carry out these usual checks:
Make sure session_start(); is called before any sessions are being called. So a safe bet would be to put it at the beginning of your page, immediately after the opening <?php declaration before anything else. Also ensure there are no whitespaces/tabs be...
Why is Git better than Subversion?
...urceSafe , I just love Subversion. Combined with TortoiseSVN , I can't really imagine how it could be any better.
30 An...
Where is the documentation for the values() method of Enum?
...places :
Enum Types, from The Java Tutorials
The compiler automatically adds some special methods when it creates
an enum. For example, they have a static values method that returns an
array containing all of the values of the enum in the order they are
declared. This method is commonl...
Check if a table exists in Rails
...? 'kittens'
In Rails 2, 3 & 4 the API is about tables.
# Listing of all tables and views
ActiveRecord::Base.connection.tables
# Checks for existence of kittens table/view (Kitten model)
ActiveRecord::Base.connection.table_exists? 'kittens'
Getting the status of migrations:
# Tells you all...
What's the fuss about Haskell? [closed]
...eems to love that language. Being good at Haskell seems somewhat like the hallmark of a genius programmer.
17 Answers
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Best way to create an empty object in JSON with PHP?
To create an empty JSON object I do usually use:
7 Answers
7
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Easy way to list node modules I have npm linked?
...ts (e.g. ls -l node_modules | grep ^l)? They're normal symlinks.
If you really need to find all symlinks, you could try something like find / -type d -name "node_modules" 2>/dev/null | xargs -I{} find {} -type l -maxdepth 1 | xargs ls -l.
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How to access the correct `this` inside a callback?
...d inside each function and its value only depends on how the function was called, not how/when/where it was defined. It is not affected by lexical scopes like other variables (except for arrow functions, see below). Here are some examples:
function foo() {
console.log(this);
}
// normal functio...
PostgreSQL naming conventions
.... Postgresql treats identifiers case insensitively when not quoted (it actually folds them to lowercase internally), and case sensitively when quoted; many people are not aware of this idiosyncrasy. Using always lowercase you are safe. Anyway, it's acceptable to use camelCase or PascalCase (or UPPER...