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How to check if a map contains a key in Go?
...ring) and ok will receive a bool that will be set to true if "foo" was actually present in the map
evaluates ok, which will be true if "foo" was in the map
If "foo" is indeed present in the map, the body of the if statement will be executed and val will be local to that scope.
...
Django MEDIA_URL and MEDIA_ROOT
... answer below; it is a better solution.
– Thane Brimhall
Apr 6 '16 at 14:14
is this in your app or project urls.py?
...
Does Dart support enumerations?
...ase Fruit.apple:
print('it is an apple');
break;
}
// get all the values of the enums
for (List<Fruit> value in Fruit.values) {
print(value);
}
// get the second value
print(Fruit.values[1]);
}
The old approach before 1.8:
class Fruit {
static const APPLE =...
How to get an object's properties in JavaScript / jQuery?
...Script's native for in loop:
var obj = {
foo: 'bar',
base: 'ball'
};
for(var key in obj) {
alert('key: ' + key + '\n' + 'value: ' + obj[key]);
}
or using jQuery's .each() method:
$.each(obj, function(key, element) {
alert('key: ' + key + '\n' + 'value: ' + element);
});
W...
Is explicitly closing files important?
In Python, if you either open a file without calling close() , or close the file but not using try - finally or the " with " statement, is this a problem? Or does it suffice as a coding practice to rely on the Python garbage-collection to close all files? For example, if one does this:
...
Dynamically updating plot in matplotlib
...out the more modern animation examples in the matplotlib documentation. Finally, the animation API defines a function FuncAnimation which animates a function in time. This function could just be the function you use to acquire your data.
Each method basically sets the data property of the object be...
how to stop browser back button using javascript
...
There are numerous reasons why disabling the back button will not really work. Your best bet is to warn the user:
window.onbeforeunload = function() { return "Your work will be lost."; };
This page does list a number of ways you could try to disable the back button, but none are guaranteed...
Maven build failed: “Unable to locate the Javac Compiler in: jre or jdk issue”
...s:
Add and set the JRE in menu Window → Preferences... → Java → Installed JREs:
JRE type: Standard VM JRE
Name: jdk1.6.0_18
JRE home directory: C:\Program Files (x86)\Java\jdk1.6.0_18
If this is not the case, it's possible that the brackets and spaces in the JAVA_HOME path are causing issu...
Getting the docstring from a function
...
On ipython or jupyter notebook, you can use all the above mentioned ways, but i go with
my_func?
or
?my_func
for quick summary of both method signature and docstring.
I avoid using
my_func??
(as commented by @rohan) for docstring and use it only to check th...
Tracking Google Analytics Page Views with AngularJS
...cs does not count it as a new page load. Fortunately there is a way to manually tell GA to log a url as a new pageview.
_gaq.push(['_trackPageview', '<url>']); would do the job, but how to bind that with AngularJS?
Here is a service which you could use:
(function(angular) {
angular.modu...