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Determine installed PowerShell version
How can I determine what version of PowerShell is installed on a computer, and indeed if it is installed at all?
19 Answers...
Chaining multiple filter() in Django, is this a bug?
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The way I understand it is that they are subtly different by design (and I am certainly open for correction): filter(A, B) will first filter according to A and then subfilter according to B, while filter(A).filter(B) will return a row that matches A...
When can I use a forward declaration?
...mpiler's position: when you forward declare a type, all the compiler knows is that this type exists; it knows nothing about its size, members, or methods. This is why it's called an incomplete type. Therefore, you cannot use the type to declare a member, or a base class, since the compiler would nee...
while (1) Vs. for (;;) Is there a speed difference?
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In perl, they result in the same opcodes:
$ perl -MO=Concise -e 'for(;;) { print "foo\n" }'
a <@> leave[1 ref] vKP/REFC ->(end)
1 <0> enter ->2
2 <;> nextstate(main 2 -e:1) v ->3
9 <2> leaveloop vK/2 ->a
3 <{> enterloop(...
Reconnection of Client when server reboots in WebSocket
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When the server reboots, the Web Socket connection is closed, so the JavaScript onclose event is triggered. Here's an example that tries to reconnect every five seconds.
function start(websocketServerLocation){
ws = new WebSocket(websocketServerLocation);
ws.onmessag...
How do I find the authoritative name-server for a domain name?
...ll want the SOA (Start of Authority) record for a given domain name, and this is how you accomplish it using the universally available nslookup command line tool:
command line> nslookup
> set querytype=soa
> stackoverflow.com
Server: 217.30.180.230
Address: 217.30.180.230#53...
.NET HashTable Vs Dictionary - Can the Dictionary be as fast?
...of them guarantee preserving the order of items.
Leaving boxing/unboxing issues aside, most of the time, they should have very similar performance.
The primary structural difference between them is that Dictionary relies on chaining (maintaining a list of items for each hash table bucket) to res...
Cannot set some HTTP headers when using System.Net.WebRequest
...t to know better, read it all, and i hope you'll enjoy...
I countered this problem too today, and what i discovered today is that:
the above answers are true, as:
1.1 it's telling you that the header you are trying to add already exist and you should then modify its value using the appropria...
JavaScript isset() equivalent
In PHP you can do if(isset($array['foo'])) { ... } . In JavaScript you often use if(array.foo) { ... } to do the same, but this is not exactly the same statement. The condition will also evaluate to false if array.foo does exists but is false or 0 (and probably other values as well).
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what is the best way to convert a json formatted key value pair to ruby hash with symbol as key?
I am wondering what is the best way to convert a json formatted key value pair to ruby hash with symbol as key:
example:
7...