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I want to get the type of a variable at runtime
...sTag example, but uses an anonymous variable.
One can also get a ClassTag from a value's Class, like this:
val x: Any = 5
val y = 5
import scala.reflect.ClassTag
def f(a: Any, b: Any) = {
val B = ClassTag(b.getClass)
ClassTag(a.getClass) match {
case B => "a is the same class as b"
...
Why does ++[[]][+[]]+[+[]] return the string “10”?
...e over +):
++[[]][0]
+
[0]
Because [[]][0] means: get the first element from [[]], it is true that:
[[]][0] returns the inner array ([]). Due to references it's wrong to say [[]][0] === [], but let's call the inner array A to avoid the wrong notation.
++ before its operand means “increment by...
Given a DateTime object, how do I get an ISO 8601 date in string format?
... @core: that's one of the standard Formats, which is different from the custom Formats linked: msdn.microsoft.com/en-us/library/az4se3k1(v=vs.110).aspx
– Wayne
Oct 29 '15 at 17:59
...
How to parse a query string into a NameValueCollection in .NET
...custom examples because of the accepted answer's dependency on System.Web. From the Microsoft.AspNet.WebApi.Client NuGet package there is a UriExtensions.ParseQueryString, method that can also be used:
var uri = new Uri("https://stackoverflow.com/a/22167748?p1=6&p2=7&p3=8");
NameValueCollec...
How to check if a map contains a key in Go?
...:
initializes two variables - val will receive either the value of "foo" from the map or a "zero value" (in this case the empty string) 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" i...
How long should SQL email fields be? [duplicate]
... software that adheres closely to
extant RFCs but accept and parse input from peers that might not be
consistent with those RFCs." - Wikipedia) when writing software that
deals with email addresses. Furthermore, some software may be crippled
by naive assumptions, e.g. thinking that 50 charac...
Rollback a Git merge
...
From here:
http://www.christianengvall.se/undo-pushed-merge-git/
git revert -m 1 <merge commit hash>
Git revert adds a new commit that rolls back the specified commit.
Using -m 1 tells it that this is a merge and w...
plot a circle with pyplot
...nd since the limits have never been set, they defaults to an x and y range from 0 to 1.
Here's a continuation of the example, showing how units matter:
circle1 = plt.Circle((0, 0), 2, color='r')
# now make a circle with no fill, which is good for hi-lighting key results
circle2 = plt.Circle((5, 5)...
Best practice for instantiating a new Android Fragment
...
From the developer docs, instantiate() Creates a new instance of a Fragment with the given class name. This is the same as calling its empty constructor.
– Brian Bowman
Feb 9 '14 at 16:1...
Round to at most 2 decimal places (only if necessary)
...ding
Solution 2 is to avoid front end calculations and pull rounded values from the backend server.
Edit: Another possible solution, which is not a bullet proof also.
Math.round((num + Number.EPSILON) * 100) / 100
In some cases, when you round number like 1.3549999999999998 it will return incorrect...