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When to use symbols instead of strings in Ruby?
...eference the symbol, saving memory. So every time the interpreter reads :my_key it can take it from memory instead of instantiate it again. This is less expensive than initializing a new string every time.
You can get a list all symbols that are already instantiated with the command Symbol.all_sym...
Should one call .close() on HttpServletResponse.getOutputStream()/.getWriter()?
...f it not closed.
public void close() throws IOException
{
if (_closed)
return;
if (!isIncluding() && !_generator.isCommitted())
commitResponse(HttpGenerator.LAST);
else
flushResponse();
super.close();
}
Also as ...
How can I make the cursor turn to the wait cursor?
...ow level.
A typical use case can look like below:
private void button1_Click(object sender, EventArgs e)
{
try
{
this.Enabled = false;//optional, better target a panel or specific controls
this.UseWaitCursor = true;//from the Form/Window instance
...
Is it possible to install iOS 6 SDK on Xcode 5?
... Older SDKs are found here.
I have copied the xcode.app directory as Xcode_4.6.3.app.
Now you can test and debug in both xcode versions. You have to run them from the corresponding folders or create shortcuts in your desktop. When building from command line give the parameter as iPhoneOS6.1 instea...
Instance variables vs. class variables in Python
...test:
import timeit
setup='''
XGLOBAL= 5
class A:
xclass = 5
def __init__(self):
self.xinstance = 5
def f1(self):
xlocal = 5
x = self.xinstance
def f2(self):
xlocal = 5
x = A.xclass
def f3(self):
xlocal = 5
x = XGLOBAL
...
MySQL case insensitive select
...ble statement this way instead: varchar(20) CHARACTER SET utf8 COLLATE utf8_bin
– gregthegeek
Mar 19 '14 at 18:56
...
java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...se 4-byte UTF8 with Connector/J configure the MySQL server with
character_set_server=utf8mb4. Connector/J will then use that setting
as long as characterEncoding has not been set in the connection
string. This is equivalent to autodetection of the character set.
Adjust your columns and datab...
How to generate an entity-relationship (ER) diagram using Oracle SQL Developer
....
Click on the «Browser» tab, expand the design (probably called Untitled_1), right-click «Relational Models» and select «New Relational Model».
Right click on the newly created relational model (probably Relational_1) and select «Show».
Then just drag the tables you want (from e.g. the «Co...
Hidden Features of C#? [closed]
...to automagically instantiate collections for me.
private IList<Foo> _foo;
public IList<Foo> ListOfFoo
{ get { return _foo ?? (_foo = new List<Foo>()); } }
share
...
An example of how to use getopts in bash
...ere it shouldn't, so change it into just h (without colon)
to expect -p any_string, you need to add p: to the argument list
Basically : after the option means it requires the argument.
The basic syntax of getopts is (see: man bash):
getopts OPTSTRING VARNAME [ARGS...]
where:
OPTSTRING is s...