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How to test if parameters exist in rails
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In Rails 5, the params object is no longer a hash, and I don't see the key? method. edgeapi.rubyonrails.org/classes/ActionController/…
– stephen.hanson
Nov 8 '16 at 22:32
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When and why should I use fragments in Android applications? [duplicate]
... parts of my applications to have their own special behavior and UI, and I don't know how fragments can help. In most cases, I think it is quicker to create 2 different activities (e.g., 1 for tablets and 1 for handsets), and to share the common behaviors and events in a third class.
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What's the easiest way to install a missing Perl module?
...tall Chocolate::Belgian
or in short form:
cpan Chocolate::Belgian
On Windows:
If you're using ActivePerl on Windows, the PPM (Perl Package Manager) has much of the same functionality as CPAN.pm.
Example:
# ppm
ppm> search net-smtp
ppm> install Net-SMTP-Multipart
see How do I insta...
Enum “Inheritance”
...if, else block would: which I think has a better better syntax anyway. You do loose ability for resharper / VS to autocomplete all the case statements, but I think that's not the end of the world. It's a personal preference but I'm not a fan of the switch statement.
– MemeDevel...
How do you determine the size of a file in C?
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Don't use int. Files over 2 gigabytes in size are common as dirt these days
Don't use unsigned int. Files over 4 gigabytes in size are common as some slightly-less-common dirt
IIRC the standard library defines off_t as an u...
How do I make a textbox that only accepts numbers?
I have a windows forms app with a textbox control that I want to only accept integer values. In the past I've done this kind of validation by overloading the KeyPress event and just removing characters which didn't fit the specification. I've looked at the MaskedTextBox control but I'd like a more g...
Why do x86-64 systems have only a 48 bit virtual address space?
...ress space even with only a few MB of physical memory; of course you could do so by swapping, or for specialized tasks where you want to map the same page at most addresses (e.g. certain sparse-data operations).
I think the real answer is that AMD was just being cheap and hoped nobody would care fo...
What character to use to put an item at the end of an alphabetic list?
... answered Feb 29 '12 at 2:37
DougDoug
44055 silver badges33 bronze badges
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Sass combining parent using ampersand (&) with type selectors
...t-root directive causes one or more rules to be emitted at the root of the document, rather than being nested beneath their parent selectors.
We can combine the @at-root directive along with interpolation #{} to arrive at the intended outcome.
SASS
.item {
color: black;
@at-root {
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How do I round a decimal value to 2 decimal places (for output on a page)
...'s accurate to like 15 decimal places, and since I'm using it to represent dollars and cents, I only want the output to be 2 decimal places.
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