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Argparse optional positional arguments?
...gt; parser.add_argument('-v', action='store_true')
_StoreTrueAction(option_strings=['-v'], dest='v', nargs=0, const=True, default=False, type=None, choices=None, help=None, metavar=None)
>>> parser.add_argument('dir', nargs='?', default=os.getcwd())
_StoreAction(option_strings=[], dest='dir...
how do you filter pandas dataframes by multiple columns
...
Note that the Gender and Year should both be strings, i.e., 'Gender' and 'Year'.
– Steven C. Howell
May 4 '17 at 19:47
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Bash, no-arguments warning, and case decisions
...s"; fi
Result
No args
Details
-z is the unary operator for length of string is zero.
$* is all arguments.
The quotes are for safety and encapsulating multiple arguments if present.
Use man bash and search (/ key) for "unary" for more operators like this.
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Struct like objects in Java
...s and setters. A possible solution would look like this:
public property String foo;
a->Foo = b->Foo;
Update: It's highly unlikely that property support will be added in Java 7 or perhaps ever. Other JVM languages like Groovy, Scala, etc do support this feature now. - Alex Miller
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Returning JSON from PHP to JavaScript?
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@FunkDoc the OP in question was stringing together JSON by hand, under the assumption that was their only choice. Knowing it wasn't their only choice was a suitable solution. There is no obligation that the end result of that JSON will be emitted as HTTP re...
Put buttons at bottom of screen with LinearLayout?
...ght="wrap_content"
android:gravity="center"
android:text="@string/cow"
android:layout_weight="0"
android:textAppearance="?android:attr/textAppearanceLarge" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dip"
...
Why should eval be avoided in Bash, and what should I use instead?
...not been rewritten as safe-for-use-in-situation-XYZ; in our case, it's any string that has not been formatted so as to be safe for evaluation.
Sanitizing data appears easy at first glance. Assuming we're throwing around a list of options, bash already provides a great way to sanitize individual el...
Swift equivalent for MIN and MAX macros
... accept any parameter type that conforms to Comparable protocol, may it be String, Character or one of your custom class or struct.
Thereby, the following Playground sample code works perfectly:
class Route: Comparable, CustomStringConvertible {
let distance: Int
var description: String {...
Maven command to list lifecycle phases along with bound goals?
...Result
.getMojoExecutionMapping();
Map<String, List<MojoExecutionKey>> phases = new LinkedHashMap<String, List<MojoExecutionKey>>();
for (MojoExecutionKey execution : mojoExecutionMapping.keySet()) {
List<MojoExe...
Will the Garbage Collector call IDisposable.Dispose for me?
... away and tested, just to make sure:
class Program
{
static void Main(string[] args)
{
Fred f = new Fred();
f = null;
GC.Collect();
GC.WaitForPendingFinalizers();
Console.WriteLine("Fred's gone, and he's not coming back...");
Console.ReadLine(...