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Double Iteration in List Comprehension

...f_words I like to think of list comprehension as stretching code horizontally. Try breaking it up into: # List Comprehension [word for sentence in text for word in sentence] Example: >>> text = (("Hi", "Steve!"), ("What's", "up?")) >>> [word for sentence in text for word in...
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check if a std::vector contains a certain object? [duplicate]

Is there something in <algorithm> which allows you to check if a std:: container contains something? Or, a way to make one, for example: ...
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receiver type *** for instance message is a forward declaration

... That basically means that you need to import the .h file containing the declaration of States. However, there is a lot of other stuff wrong with your code. You're -init'ing an object without +alloc'ing it. That won't work You're dec...
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Swift Programming: getter/setter in stored property

...the new value that you assign will replace the one that was just set. So all you have to do is this: var rank: Int = 0 { didSet { // Say 1000 is not good for you and 999 is the maximum you want to be stored there if rank >= 1000 { rank = 999 } } } ...
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Why are there no ++ and --​ operators in Python?

...to give it its own special syntax; when you do need to increment, += is usually just fine. It's not a decision of whether it makes sense, or whether it can be done--it does, and it can. It's a question of whether the benefit is worth adding to the core syntax of the language. Remember, this is fo...
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String.Replace ignoring case

I have a string called "hello world" 16 Answers 16 ...
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Django set default form values

...ch is explained here You have two options either populate the value when calling form constructor: form = JournalForm(initial={'tank': 123}) or set the value in the form definition: tank = forms.IntegerField(widget=forms.HiddenInput(), initial=123) ...
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GLib compile error (ffi.h), but libffi is installed

... If you have a Debian-based Linux OS with apt-get: sudo apt-get install libffi-dev With a Redhat-base OS: yum install libffi-devel With Alpine Linux: apk add libffi-dev share | improve...
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Difference between \w and \b regular expression meta characters

...chor like the caret and the dollar sign. It matches at a position that is called a "word boundary". This match is zero-length. There are three different positions that qualify as word boundaries: Before the first character in the string, if the first character is a word character. After the last ...
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Case objects vs Enumerations in Scala

... deal with an Option[Currency] type that would clearly indicate there is really a matching problem and "encourage" the user of the API to sort it out him/herself. To follow up on the other answers here, the main drawbacks of case objects over Enumerations are: Can't iterate over all instances of t...