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Objective-C: difference between id and void *
What is the difference between id and void * ?
7 Answers
7
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Java optional parameters
... by the possibility of more than one return value.
– Andreas Vogl
Dec 26 '19 at 11:05
Adding global variables might ca...
Argparse: Required arguments listed under “optional arguments”?
...sually considered optional. All other parameters are positional parameters and as such required by design (like positional function arguments). It is possible to require optional arguments, but this is a bit against their design. Since they are still part of the non-positional arguments, they will s...
Match multiple cases classes in scala
I'm doing matching against some case classes and would like to handle two of the cases in the same way. Something like this:
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Default height for section header in UITableView
...hmm.. As for me UITableViewAutomaticDimension returns -1 (hardcoded const) and I don't see any sections at all in my UITableView.
– skywinder
Sep 22 '13 at 21:17
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Laravel Check If Related Model Exists
...$relation) is a general solution for all relations. It will work for Model and Collection, while Model has no ->count() method.
– Jarek Tkaczyk
Jul 29 '14 at 17:16
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What is difference between monolithic and micro kernel?
Could anyone please explain with examples difference between monolithic and micro kernel? Also other classifications of the kernel?
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How to do associative array/hashing in JavaScript
...h new Array() is frowned up. The article eventually mentions its drawbacks and suggests new Object() or {} as preferred alternatives, but that's near the end and I fear most readers won't get that far.
– Daniel Lubarov
May 16 '15 at 5:55
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Create PostgreSQL ROLE (user) if it doesn't exist
...sword';
END IF;
END
$do$;
(Building on @a_horse_with_no_name's answer and improved with @Gregory's comment.)
Unlike, for instance, with CREATE TABLE there is no IF NOT EXISTS clause for CREATE ROLE (up to at least pg 12). And you cannot execute dynamic DDL statements in plain SQL.
Your reques...
How do I check two or more conditions in one ?
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If you are using JSP 2.0 and above It will come with the EL support:
so that you can write in plain english and use and with empty operators to write your test:
<c:if test="${(empty object_1.attribute_A) and (empty object_2.attribute_B)}">
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