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Left-pad printf with spaces
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If you want the word "Hello" to print in a column that's 40 characters wide, with spaces padding the left, use the following.
char *ptr = "Hello";
printf("%40s\n", ptr);
That will give you 35 spaces, then the word "Hello". This is how you format stuff when you know how wide you wa...
Type erasure techniques
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I would also consider (similar to void*) the use of "raw storage": char buffer[N].
In C++0x you have std::aligned_storage<Size,Align>::type for this.
You can store anything you want in there, as long as it's small enough and you deal with the alignment properly.
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jquery select change event get selected option
I bound an event on the change event of my select elements with this:
9 Answers
9
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What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
...Core Foundation objects and memory allocated using malloc() for types like char*. ARC does not manage these types, only Objective-C objects, so you'll still need to deal with them yourself. Core Foundation types can be particularly tricky, because sometimes they need to be bridged across to matchi...
Filtering for empty or NULL names in a queryset
...null, not-empty alias field. The generated SQL would look something like:
SELECT * FROM Name WHERE alias IS NOT NULL AND alias != ""
You can also pass multiple arguments to a single call to exclude, which would ensure that only objects that meet every condition get excluded:
Name.objects.exclude...
Is a Java string really immutable?
.... However, looking at the source code of String, we can see that the value character array for a substring is actually copied (using Arrays.copyOfRange(..)). This is why it goes unchanged.
You can install a SecurityManager, to avoid malicious code to do such things. But keep in mind that some libra...
How to Create Multiple Where Clause Query Using Laravel Eloquent?
...;orWhere($orThose)
->get();
The above will result in such query:
SELECT * FROM users
WHERE (field = value AND another_field = another_value AND ...)
OR (yet_another_field = yet_another_value AND ...)
share
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How to pull a random record using Django's ORM?
...on't know about other databases).
order_by('?')[:N] will be translated to SELECT ... FROM ... WHERE ... ORDER BY RAND() LIMIT N query.
It means that for every row in table the RAND() function will be executed, then the whole table will be sorted according to value of this function and then first N...
Where is array's length property defined?
...he StringBuffer class itself does, yes - because it holds a reference to a char[] (or did, at least; I don't know whether it still does, off-hand). So while a StringBuilder is responsible for more memory, its immediate size and layout are fixed.
– Jon Skeet
Sep...
Using varchar(MAX) vs TEXT on SQL Server
...es ('b')
insert into @table values ('c')
insert into @table values ('d')
select *
from @table
where a ='a'
This give an error:
The data types text and varchar are incompatible in the equal to operator.
Wheras this does not:
declare @table table (a varchar(max))
Interestingly, LIKE still wo...