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Append class if condition is true in Haml
If post.published?
5 Answers
5
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Google Guava isNullOrEmpty for collections
...mpty" is a question you ever really want to be asking about a collection.
If a collection might be null, and null should be treated the same as empty, then get all that ambiguity out of the way up front, like this:
Set<Foo> foos = NaughtyClass.getFoos();
if (foos == null) {
foos = Immutabl...
How do you check “if not null” with Eloquent?
How do you check if a field is not null with Eloquent?
7 Answers
7
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getActivity() returns null in Fragment function
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I didn't understand how you can solve your problem. If my getActivity() isn't stille ready, how can I get the reference of FragmentActivity object?
– CeccoCQ
Aug 8 '11 at 10:12
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Detect Retina Display
Does iOS SDK provides an easy way to check if the currentDevice has an high-resolution display (retina) ?
14 Answers
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Check if string contains only digits
I want to check if a string contains only digits. I used this:
14 Answers
14
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How does one write code that best utilizes the CPU cache to improve performance?
... could sound like a subjective question, but what I am looking for are specific instances, which you could have encountered related to this.
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How do you remove an array element in a foreach loop?
I want to loop through an array with foreach to check if a value exists. If the value does exist, I want to delete the element which contains it.
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Mysql: Select rows from a table that are not in another
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If you have 300 columns as you mentioned in another comment, and you want to compare on all columns (assuming the columns are all the same name), you can use a NATURAL LEFT JOIN to implicitly join on all matching column names...
How to find all duplicate from a List? [duplicate]
... is not complete, that one is just the first step. Then he can use a Where if he wants just the duplicates, like list.GroupBy(x => x).Where(group => group.Count() > 1).Select(group => Group.Key).ToList()
– Giuseppe Ottaviano
Jan 2 '11 at 12:34
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