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GOBIN not set: cannot run go install
I am trying to install my custom package for my main.go file. However, when I ran
13 Answers
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Ruby on Rails: How do I add a not null constraint to an existing column using a migration?
In my Rails (3.2) app, I have a bunch of tables in my database but I forgot to add a few not null constraints. I've googled around but I can't find how to write a migration which adds not null to an existing column.
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Creating and throwing new exception
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To call a specific exception such as FileNotFoundException use this format
if (-not (Test-Path $file))
{
throw [System.IO.FileNotFoundException] "$file not found."
}
To throw a general exception use the throw command followed by a string.
throw "Error trying to do a task"
When used ...
Transparent background with three.js
The code work, but I'm having a problem setting transparent background to the canvas with three.js. I use:
1 Answer
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Spring MVC @PathVariable with dot (.) is getting truncated
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As far as i know this issue appears only for the pathvariable at the end of the requestmapping.
We were able to solve that by defining the regex addon in the requestmapping.
/somepath/{variable:.+}
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Insert new item in array on any position in PHP
How can I insert a new item into an array on any position, for example in the middle of array?
18 Answers
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A good book for learning D3.js [closed]
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As @Autio already mentioned, there are the tutorials from Scott Murray on his website.
You will also note that on his site, he has a link to his recent d3 book,
Interactive Data Visualization for the Web.
However, that book is now available online for free, along wit...
Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
... some code that marked a member variable of a class with the mutable keyword. As far as I can see it simply allows you to modify a variable in a const method:
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How to get the current time in Python
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Use:
>>> import datetime
>>> datetime.datetime.now()
datetime.datetime(2009, 1, 6, 15, 8, 24, 78915)
>>> print(datetime.datetime.now())
2009-01-06 15:08:24.789150
And just the time:
>>> datetime.datetime.no...
Clojure: cons (seq) vs. conj (list)
...ap as soon as it grows beyond 9 entries.)
1 Traditionally, in the Lisp world, cons cons(tructs a pair), so Clojure departs from the Lisp tradition in having its cons function construct a seq which doesn't have a traditional cdr. The generalised usage of cons to mean "construct a record of some ty...