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What is “lifting” in Scala?
...unately, it is not explained what that exactly means. I did some research, and it seems that lifting has something to do with functional values or something like that, but I was not able to find a text that explains what lifting actually is about in a beginner friendly way.
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Show just the current branch in Git
I tried looking for a special Git command for this, but I couldn't find one. Is there anything shorter or faster than the following?
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Creating a new column based on if-elif-else condition
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Thank you, I am beginning with pandas and this was very helpful +1
– nutship
Feb 12 '14 at 8:18
4
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Using regular expressions to parse HTML: why not?
...ossible with regular expressions, since it depends on matching the opening and the closing tag which is not possible with regexps.
Regular expressions can only match regular languages but HTML is a context-free language and not a regular language (As @StefanPochmann pointed out, regular languages a...
MySQL: Set user variable from result of query
...rator. However inside other statements, the assignment operator must be := and not = because = is treated as a comparison operator in non-SET statements.
UPDATE:
Further to comments below, you may also do the following:
SET @user := 123456;
SELECT `group` FROM user LIMIT 1 INTO @group;
SELECT ...
Why does document.querySelectorAll return a StaticNodeList rather than a real Array?
...n't just do document.querySelectorAll(...).map(...) even in Firefox 3.6, and I still can't find an answer, so I thought I'd cross-post on SO the question from this blog:
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What is __main__.py?
...hat is the __main__.py file for, what sort of code should I put into it, and when should I have one?
5 Answers
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JsonMappingException: out of START_ARRAY token
...is malformed: the type of center is an array of invalid objects. Replace [ and ] with { and } in the JSON string around longitude and latitude so they will be objects:
[
{
"name" : "New York",
"number" : "732921",
"center" : {
"latitude" : 38.895111,
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NULL vs nil in Objective-C
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nil should only be used in place of an id, what we Java and C++ programmers would think of as a pointer to an object. Use NULL for non-object pointers.
Look at the declaration of that method:
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object
change:(NSDi...
Git diff between current branch and master but not including unmerged master commits
...How can I see what branch another branch was forked from?
Note that .. and ... syntax does not have the same semantics as in other Git tools. It differs from the meaning specified in man gitrevisions.
Quoting man git-diff:
git diff [--options] <commit> <commit> [--] [<path...