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Issue with virtualenv - cannot activate
...cannot.
It might just be syntax or folder location, but I am stumped right now.
21 Answers
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What does the JSLint error 'body of a for in should be wrapped in an if statement' mean?
...ethods. Lots of libraries do this.
However, let's look at how for in works now:
var listeners = ["a", "b", "c"];
for (o in listeners) {
console.log(o);
}
//prints:
// 0
// 1
// 2
// filter_0
Do you see? It suddenly thinks filter_0 is another array index. Of course, it is not really a nume...
JPA CascadeType.ALL does not delete orphans
... all child elements
delete main row
close session
With JPA 2.0, you can now use the option orphanRemoval = true
@OneToMany(mappedBy="foo", orphanRemoval=true)
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How to implement common bash idioms in Python? [closed]
...I just discovered how to combine the best parts of bash and ipython. Up to now this seems more comfortable to me than using subprocess and so on. You can easily copy big parts of existing bash scripts and e.g. add error handling in the python way :)
And here is my result:
#!/usr/bin/env ipython3
#...
What are the differences between JSON and JSONP?
... This is usually used to allow for cross-site AJAX with JSON data. If you know that example.com is serving JSON files that look like the JSONP example given above, then you can use code like this to retrieve it, even if you are not on the example.com domain:
function func(json){
alert(json.name);...
Efficient SQL test query or validation query that will work across all (or most) databases
...g_table WHERE 1=0
or
SELECT 1 FROM INFORMATION_SCHEMA.SYSTEM_USERS
or
CALL NOW()
HSQLDB (tested with version 1.8.0.10)
Note: I tried using a WHERE 1=0 clause on the second query, but it didn't work as a value for Apache Commons DBCP's validationQuery, since the query doesn't return any rows
VAL...
SQL Server: Get data for only the past year
... opinion, data from the last year is every data from 2007 (if I am in 2008 now). So the right answer would be:
SELECT ... FROM ... WHERE YEAR(DATE) = YEAR(GETDATE()) - 1
Then if you want to restrict this query, you can add some other filter, but always searching in the last year.
SELECT ... FROM...
autolayout - make height of view relative to half superview height
...
This is now possible in IB as of [at least] Xcode 5.1.1. Although it took me sometime to figure out it is actually super simple:
First create a basic top alignment constraint (you will also need to setup bottom, left, and right cons...
NoClassDefFoundError: android.support.v7.internal.view.menu.MenuBuilder
... I've been using a solution from that issue report for months now and all of the sudden after updating to the latest support libraries and sdk 23 I've started getting this new report on crashlytics: java.lang.NoClassDefFoundError: android.support.v7.internal.view.menu.i
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Programmatically creating Markdown tables in R with KnitR
...ng (sort of like xtable , but with Markdown instead of LaTeX or HTML). I know that I can just embed the HTML output from xtable, but I was wondering if there were any Markdown-based solutions?
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