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Is it possible to delete an object's property in PHP?
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unset($a->new_property);
This works for array elements, variables, and object attributes.
Example:
$a = new stdClass();
$a->new_property = 'foo';
var_export($a); // -> stdClass::__set_state(array('new_property' => 'foo'))
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Case objects vs Enumerations in Scala
...nswered Dec 14 '09 at 9:27
oxbow_lakesoxbow_lakes
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The character encoding of the HTML document was not declared
... edited Sep 27 '15 at 8:04
joe_young
3,79022 gold badges2020 silver badges3434 bronze badges
answered Sep 27 '15 at 7:08
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Why does sudo change the PATH?
... Don't alias sudo; see answer from @Jacob about Defaults env_reset.
– greg_1_anderson
Aug 19 '12 at 18:35
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show 7 more comme...
how to “reimport” module to python then code be changed after import
...port sys then reload(sys.modules['foo']) or perhaps reload(sys.modules[bar.__module__])
– drevicko
Oct 28 '13 at 1:02
3
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Get underlined text with Markdown
... answered Jun 9 '10 at 6:24
zed_0xffzed_0xff
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Right way to reverse pandas.DataFrame?
...ata.Odd[idx])
You are getting an error because reversed first calls data.__len__() which returns 6. Then it tries to call data[j - 1] for j in range(6, 0, -1), and the first call would be data[5]; but in pandas dataframe data[5] means column 5, and there is no column 5 so it will throw an exceptio...
Insert, on duplicate update in PostgreSQL?
...FLICT clause. with the following syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group a...
std::unique_lock or std::lock_guard?
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The difference is that you can lock and unlock a std::unique_lock. std::lock_guard will be locked only once on construction and unlocked on destruction.
So for use case B you definitely need a std::unique_lock for the condition variable. In case A it depends whether you need to relo...
Finding the type of an object in C++
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dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime...