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How to detect if a function is called as constructor?
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NOTE: This is now possible in ES2015 and later. See Daniel Weiner's answer.
I don't think what you want is possible [prior to ES2015]. There simply isn't enough information available within the function to make a reliable inference.
Looking at the ECMAScript 3...
PostgreSQL Crosstab Query
... , status text
, ct integer -- "count" is a reserved word in standard SQL
);
INSERT INTO tbl VALUES
('A', 'Active', 1), ('A', 'Inactive', 2)
, ('B', 'Active', 4), ('B', 'Inactive', 5)
, ('C', 'Inactive', 7); -- ('C', 'Active') is missing
Simple form - not fit f...
How do I get and set Environment variables in C#?
How can I get Environnment variables and if something is missing, set the value?
6 Answers
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In Ruby, is there an Array method that combines 'select' and 'map'?
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I usually use map and compact together along with my selection criteria as a postfix if. compact gets rid of the nils.
jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1}
=> [3, 3, 3, nil, nil, nil]
jruby-1.5.0 > [1,1,1,2,3,4].m...
Is JavaScript's “new” keyword considered harmful?
... question , a user pointed out that the new keyword was dangerous to use and proposed a solution to object creation that did not use new . I didn't believe that was true, mostly because I've used Prototype, Scriptaculous and other excellent JavaScript libraries, and everyone of them used the new...
nginx: [emerg] could not build the server_names_hash, you should increase server_names_hash_bucket_s
...nde-einbeck.de as a virtual host. I already have 2 other domains in there and it works fine, but when I try to add the above mentioned domain and start the server it gives me Job failed. See system journal and 'systemctl status' for details.
I thought it was because of the dashes, so I tried jus...
MongoDB inserts float when trying to insert integer
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If the value type is already double, then update the value with $set command can not change the value type double to int when using NumberInt() or NumberLong() function.
So, to Change the value type, it must update the whole record.
var re = db.data.find({"name": "zero"})
re['value']=NumberInt(0)...
'nuget' is not recognized but other nuget commands working
...nuget package using http://docs.nuget.org/docs/creating-packages/creating-and-publishing-a-package#From_a_convention_based_working_directory
as a reference.
My Package Manger Console in Visual Studio is not allowing me to use the 'nuget' command.
I am able to 'Get-help nuguet' and it displays:
...
What is a good reason to use SQL views?
I am reading through the SQL Server 2008 bible and I am covering the views section. But the author really doesn't explain the purpose of views. What is a good use for views? Should I use them in my website and what are the benefits of them?
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Why are local variables not initialized in Java?
...ulation. So its the programmer's decision to set the value of the variable and it should not take a default value. If the programmer, by mistake, did not initialize a local variable and it take default value, then the output could be some unexpected value. So in case of local variables, the compiler...