Maps and Sets are not well suited for random access. They are ordered and their length is known, but they are not indexed for access by an order index. As such, to get the Nth item in a Map or Set, you have to iterate through it to find that item. The simple way to … Read more
Using list comprehension is maybe more “pythonic”. filtered = [x for x in set(lst) if x < C]
Nope. But I here is how to clean it up. First, rewrite iterator based functions as ranged based functions. This halves your boilerplate. Second, have them return container builders rather than take insert iterators: this gives you efficient assignment syntax. Third, and probably too far, write them as named operators. The final result is you … Read more
Are you looking for Sets.immutableEnumSet (Guava) perhaps? Returns an immutable set instance containing the given enum elements. Internally, the returned set will be backed by an EnumSet. The iteration order of the returned set follows the enum’s iteration order, not the order in which the elements appear in the given collection.
You can check the value of $- to see the current options; if it contains an x, it was set. You can check like so: old_setting=${-//[^x]/} … if [[ -n “$old_setting” ]]; then set -x; else set +x; fi In case it’s not familiar to you: the ${} above is a Bash Substring Replacement, which … Read more
for future googlers! finally i managed to solve the problem, i just had to put the annotations somewhere else in my code , @ElementCollection(targetClass = Days.class) @CollectionTable(name = “days”, joinColumns = @JoinColumn(name = “rule_id”)) @Column(name = “daysOfWeek”, nullable = false) @Enumerated(EnumType.STRING) public Set<Days> getDays() { return days; } as you can see i wrote the … Read more
You should watch this video (although it is CPython1 specific and about dictionaries — but I assume it applies to sets as well). Basically, python hashes the elements and takes the last N bits (where N is determined by the size of the set) and uses those bits as array indices to place the object … Read more
It’s because unordered_set is using std::hash template to compute hash for its entries and there is no std::hash for pairs. You have to define custom hash to use unordered_set. struct vector_hash { template <class T1, class T2> std::size_t operator () (std::pair<T1, T2> const &v) const { return std::hash<T1>()(v.size()); } }; and then declare your unordered_set … Read more
You could do this using JSTL tags, but the result is not optimal: <%@ taglib prefix=”c” uri=”http://java.sun.com/jsp/jstl/core”%> <html> <body> <jsp:useBean id=”numbers” class=”java.util.HashSet” scope=”request”> <% numbers.add(“one”); numbers.add(“two”); numbers.add(“three”); %> </jsp:useBean> <c:forEach items=”${numbers}” var=”value”> <c:if test=”${value == ‘two’}”> <c:set var=”found” value=”true” scope=”request” /> </c:if> </c:forEach> ${found} </body> </html> A better way would be to use a custom … Read more
You can write a single element tuple as @larsmans explained, but it is easy to forget the trailing comma. It may be less error prone if you just use lists as the parameters to the set constructor and methods: Dictionary[key_1] = set([‘name’]) Dictionary[key_2] = set([‘name_2’, ‘name_3’]) Dictionary[key_2].add([‘name_3’]) should all work the way you expect.