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Why does Clojure have “keywords” in addition to “symbols”?
I have a passing knowledge of other Lisps (particularly Scheme) from way back. Recently I've been reading about Clojure . I see that it has both "symbols" and "keywords". Symbols I'm familiar with, but not with keywords.
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How to configure slf4j-simple
api 1.7 and slf4j-simple as implementation. I just can't find how to configure the logging level with this combination.
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What is the “owning side” in an ORM mapping?
What exactly does the owning side mean? What is an explanation with some mapping examples ( one to many, one to one, many to one )?
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Why does the MongoDB Java driver use a random number generator in a conditional?
I saw the following code in this commit for MongoDB's Java Connection driver , and it appears at first to be a joke of some sort. What does the following code do?
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Subset of rows containing NA (missing) values in a chosen column of a data frame
We have a data frame from a CSV file. The data frame DF has columns that contain observed values and a column ( VaR2 ) that contains the date at which a measurement has been taken. If the date was not recorded, the CSV file contains the value NA , for missing data.
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Elastic search, multiple indexes vs one index and types for different data sets?
I have an application developed using the MVC pattern and I would like to index now multiple models of it, this means each model has a different data structure.
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How to find duplicates in 2 columns not 1
I have a MySQL database table with two columns that interest me. Individually they can each have duplicates, but they should never have a duplicate of BOTH of them having the same value.
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Should I pass an std::function by const-reference?
Let's say I have a function which takes an std::function :
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Why does casting int to invalid enum value NOT throw exception?
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How can I get a Bootstrap column to span multiple rows?
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