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Checking if a variable is not nil and not zero in ruby
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You could do this:
if (!discount.nil? && !discount.zero?)
The order is important here, because if discount is nil, then it will not have a zero? method. Ruby's short-circuit evaluation should prevent it from trying to evaluate discount.zero?, however, if discount is nil.
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How does Python 2 compare string and int? Why do lists compare as greater than numbers, and tuples g
...ython implementation detail: Objects of different types except numbers are ordered by their type names; objects of the same types that don’t support proper comparison are ordered by their address.
When you order two strings or two numeric types the ordering is done in the expected way (lexicogra...
Objective-C: Property / instance variable in category
...just an extension to it that avoids writing too much boilerplate code.
In order to avoid writing repeatedly getter and setter methods for category properties this answer introduces macros. Additionally these macros ease the use of primitive type properties such as int or BOOL.
Traditional approach...
Why does Java's hashCode() in String use 31 as a multiplier?
...cation to be key.hashCode() ^ value.hashCode() despite it is not even an unordered pair, as key and value have entirely different meaning. Yes, that implies that Map.of(42, 42).hashCode() or Map.of("foo", "foo", "bar", "bar").hashCode(), etc, are predictably zero. So don’t use maps as keys for oth...
What's the difference between comma separated joins and join on syntax in MySQL? [duplicate]
...same query. If we do mix them, we need to be aware of a difference in the order of precedence.
excerpt from MySQL Reference Manual
https://dev.mysql.com/doc/refman/5.6/en/join.html
INNER JOIN and , (comma) are semantically equivalent in the absence of a join condition: both produce a Cartesian pro...
Find most frequent value in SQL column
...) AS `value_occurrence`
FROM `my_table`
GROUP BY `column`
ORDER BY `value_occurrence` DESC
LIMIT 1;
Replace column and my_table. Increase 1 if you want to see the N most common values of the column.
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Could not establish trust relationship for SSL/TLS secure channel — SOAP
...w machine is not a server -- it is a desktop running my app, which gathers order info and uploads via the SOAP service 3) Yes, we can browse to it. 4) This is new to me: machine level proxy?
– Rob Schripsema
Mar 31 '09 at 22:21
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How do I change Bootstrap 3 column order on mobile layout?
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You cannot change the order of columns in smaller screens but you can do that in large screens.
So change the order of your columns.
<!--Main Content-->
<div class="col-lg-9 col-lg-push-3">
</div>
<!--Sidebar-->
<div ...
java.util.regex - importance of Pattern.compile()?
...d reset a Matcher object that is only ever used by one thread at a time in order to reduce allocations.
– AndrewF
Jul 3 '19 at 20:40
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When to use Preorder, Postorder, and Inorder Binary Search Tree Traversal strategies
...BST's plenty in my life, I've never even contemplated using anything but Inorder traversal (while I am aware of and know how easy it is to adapt a program to use pre/post-order traversal).
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