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Good examples of Not a Functor/Functor/Applicative/Monad?
...ariant functor out of it, but not a (covariant) functor. Try writing fmap and you'll fail. Note that the contravariant functor version is reversed:
fmap :: Functor f => (a -> b) -> f a -> f b
contramap :: Contravariant f => (a -> b) -> f b -> f a
A type constr...
How to import other Python files?
...t__): Because this function is meant for use by the Python interpreter and not for general use it is better to use importlib.import_module() to programmatically import a module.
– Tadhg McDonald-Jensen
Feb 23 '16 at 15:04
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Can you remove elements from a std::list while iterating through it?
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You have to increment the iterator first (with i++) and then remove the previous element (e.g., by using the returned value from i++). You can change the code to a while loop like so:
std::list<item*>::iterator i = items.begin();
while (i != items.end())
{
bool isA...
Create array of regex matches
...an the below if you can assume Java >= 9)
You need to create a matcher and use that to iteratively find matches.
import java.util.regex.Matcher;
import java.util.regex.Pattern;
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List<String> allMatches = new ArrayList<String>();
Matcher m = Pattern.compile("your regular ex...
What is a “bundle” in an Android application
What is a bundle in an Android application? When to use it?
12 Answers
12
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Each for object? [duplicate]
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A javascript Object does not have a standard .each function. jQuery provides a function. See http://api.jquery.com/jQuery.each/ The below should work
$.each(object, function(index, value) {
console.log(value);
});
Another option would be to use vanilla Ja...
How do I (or can I) SELECT DISTINCT on multiple columns?
...on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
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node.js global variables?
... if you really want to use them. The 3 statements below are all equivalent and will assign a var to the global scope: GLOBAL._ = require('underscore'); global._ = require('underscore'); _ = require('underscore');
– metaColin
Aug 5 '15 at 18:23
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Simplest SOAP example
... This worked for me! (after replacing the SOAP Service URL with a real one and turning off cross-domain restrictions on my browser, as implied by @Prestaul)
– Niko Bellic
Dec 9 '14 at 19:44
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How do you use “
I just finished reading about scoping in the R intro , and am very curious about the <<- assignment.
6 Answers
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