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The differences between .build, .create, and .create! and when should they be used?
... people using .build , .create , and .create! within their controllers more and more lately. What's the difference from just using .new and passing the param'd object and then .save ? Are there pros and cons? Does using these other m>me m>thods offer benefits?
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Split list into multiple lists with fixed number of elem>me m>nts
How to split a List of elem>me m>nts into lists with at most N items?
5 Answers
5
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Process all argum>me m>nts except the first one (in a bash script)
I have a simple script where the first argum>me m>nt is reserved for the filenam>me m>, and all other optional argum>me m>nts should be passed to other parts of the script.
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Why does Convert.ToString(null) return a different value if you cast null?
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There are 2 overloads of ToString that com>me m> into play here
Convert.ToString(object o);
Convert.ToString(string s);
The C# compiler essentially tries to pick the most specific overload which will work with the input. A null value is convertible to any reference t...
C++ unordered_map using a custom class type as the key
I am trying to use a custom class as key for an unordered_map , like the following:
3 Answers
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Why does the C++ map type argum>me m>nt require an empty constructor when using []?
Not a major issue, just annoying as I don't want my class to ever be instantiated without the particular argum>me m>nts.
5 Answe...
Multiple columns index when using the declarative ORM extension of sqlalchemy
According to the docum>me m>ntation and the comm>me m>nts in the sqlalchemy.Column class, we should use the class sqlalchemy.schema.Index to specify an index that contains multiple columns.
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What is the advantage to using bloom filters?
...rings (tries are an exception, since
they can share storage between
elem>me m>nts with equal prefixes). Linked
structures incur an additional linear
space overhead for pointers. A Bloom
filter with 1% error and an optimal
value of k, on the other hand,
requires only about 9.6 bits per
ele...
BigDecimal - to use new or valueOf
I cam>me m> across two ways of getting BigDecimal object out of a double d.
3 Answers
3
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instantiate a class from a variable in PHP?
I know this question sounds rather vague so I will make it more clear with an example:
5 Answers
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