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Error installing mysql2: Failed to build gem native extension
I am having some problems when trying to install mysql2 gem for Rails. When I try to install it by running bundle install or gem install mysql2 it gives me the following error:
...
Python: Find in list
...e which suffers from inaccuracy.
As for your second question: There's actually several possible ways if "finding" things in lists.
Checking if something is inside
This is the use case you describe: Checking whether something is inside a list or not. As you know, you can use the in operator for th...
Can not connect to local PostgreSQL
...
This really looks like a file permissions error. Unix domain sockets are files and have user permissions just like any other. It looks as though the OSX user attempting to access the database does not have file permissions to acce...
What does the “@” symbol mean in reference to lists in Haskell?
...hout the @, you'd have to choose between (1) or (2):(3).
This syntax actually works for any constructor; if you have data Tree a = Tree a [Tree a], then t@(Tree _ kids) gives you access to both the tree and its children.
s...
Signed to unsigned conversion in C - is it always safe?
...herwise, if the type of the operand with signed integer type can represent all of the values of the type of the operand with unsigned integer type, then the operand with unsigned integer type is converted to the type of the operand with signed integer type.
Otherwise, both operands are converted t...
How do I associate a Vagrant project directory with an existing VirtualBox VM?
...othername".
Stop the machine from provisioning:
Create a file named action_provision in the same dir as the id file, set it's contents to: 1.5:{id} replacing {id} with the id found in step 1.
Setup a new public/private key:
Vagrant uses a private key stored in .vagrant/machines/default/virtualbox/...
How to save a PNG image server-side, from a base64 data string
...plode(';', $data);
list(, $data) = explode(',', $data);
$data = base64_decode($data);
file_put_contents('/tmp/image.png', $data);
And as a one-liner:
$data = base64_decode(preg_replace('#^data:image/\w+;base64,#i', '', $data));
An efficient method for extracting, decoding, and checking for e...
Unique Constraint in Entity Framework Code First
...
CreateIndex("TableName", new string[2] { "Column1", "Column2" }, true, "IX_UniqueColumn1AndColumn2");
Something like that:
namespace Sample.Migrations
{
using System;
using System.Data.Entity.Migrations;
public partial class TableName_SetUniqueCompositeIndex : DbMigration
{
...
Is there a way to suppress warnings in Xcode?
...his overrides any warning flags on the command line. It doesn't work with all warnings though. Add -fdiagnostics-show-option to your CFLAGS and you can see which flag you can use to disable that warning.
share
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Change Screen Orientation programmatically using a Button
..._PORTRAIT works properly on tablets.
Note: this feature was introduced in API Level 9, so if you must support 8 or lower (not likely at this point), then instead use:
setRequestedOrientation(Build.VERSION.SDK_INT < 9 ?
ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE :
...