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Ruby - elegantly convert variable to an array if not an array already
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@mastaBlasta Array(arg) tries to create a new array by calling to_ary, then to_a on the argument. This is documented in official ruby docs. I learned about it from Avdi's "Confident Ruby" book.
– mambo
Jul 27 '16 at 15:41
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“No newline at end of file” compiler warning
... preceded by a backslash character before any such splicing takes place, shall be processed as if an additional new-line character were appended to the file (C++11 §2.2/1).
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Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
... 'pancakes house?' }
The JavaScript style (key: value) is only useful if all of your Hash keys are "simple" symbols (more or less something that matches /\A[a-z_]\w*\z/i, AFAIK the parser uses its label pattern for these keys).
The :$in style symbols show up a fair bit when using MongoDB so you'l...
How to check for the type of a template parameter?
...::is_same<T, animal>::value) { /* ... */ } // optimizable...
}
Usually, that's a totally unworkable design, though, and you really want to specialize:
template <typename T> void foo() { /* generic implementation */ }
template <> void foo<animal>() { /* specific for T ...
[] and {} vs list() and dict(), which is better?
...> timeit("list((1,2,3))")
0.44744206316727286
>>> timeit("list(foo)", setup="foo=(1,2,3)")
0.446036018543964
>>> timeit("{'a':1, 'b':2, 'c':3}")
0.20868602015059423
>>> timeit("dict(a=1, b=2, c=3)")
0.47635635255323905
>>> timeit("dict(bar)", setup="bar=[('a', ...
How can I avoid Java code in JSP files, using JSP 2?
...ance/composition.
Debuggability: if scriptlet throws an exception halfway, all you get is a blank page.
Testability: scriptlets are not unit-testable.
Maintainability: per saldo more time is needed to maintain mingled/cluttered/duplicated code logic.
Sun Oracle itself also recommends in the JSP co...
How to retrieve inserted id after inserting row in SQLite using Python?
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There is also the last_insert_rowid() SQL function, allowing you to insert the last row id as a foreign key in a next insert statement, entirely in SQL.
– Martijn Pieters♦
Feb 3 '14 at 12:36
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Run an OLS regression with Pandas Data Frame
...swered Nov 16 '13 at 14:14
Fred FooFred Foo
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?: operator (the 'Elvis operator') in PHP
... left operand is truthy, and the right operand otherwise.
In pseudocode,
foo = bar ?: baz;
roughly resolves to
foo = bar ? bar : baz;
or
if (bar) {
foo = bar;
} else {
foo = baz;
}
with the difference that bar will only be evaluated once.
You can also use this to do a "self-check"...
Passing just a type as a parameter in C#
...ic T GetColumnValue<T>(this string columnName){...} then you can say foo.GetColumnValues<string>(dm.mainColumn)
– Joshua G
Jun 4 '14 at 15:56
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