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Questions tagged [nested]

This tag relates to any of various nested entities or operations in programming.

This tag relates to any of various nested entities in programming, including but not limited to:

  • Nested data structures
  • Nested queries
  • Nested calls to a procedure, subroutine, method or operation

For example, nesting queries in SQL means to create a subquery. Its result is used in the query itself and provides a query order and subsets.

Related tags :

14133 questions
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How can I access and process nested objects, arrays or JSON?

I have a nested data structure containing objects and arrays. How can I extract the information, i.e. access a specific or multiple values (or keys)? For example: var data = { code: 42, items: [{ id: 1, name: 'foo' }, { …
Felix Kling
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Test for existence of nested JavaScript object key

If I have a reference to an object: var test = {}; that will potentially (but not immediately) have nested objects, something like: {level1: {level2: {level3: "level3"}}}; What is the best way to check for the existence of property in deeply…
user113716
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Accessing nested JavaScript objects and arrays by string path

I have a data structure like this : var someObject = { 'part1' : { 'name': 'Part 1', 'size': '20', 'qty' : '50' }, 'part2' : { 'name': 'Part 2', 'size': '15', 'qty' : '60' }, …
Komaruloh
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Margin on child element moves parent element

I have a div (parent) that contains another div (child). Parent is the first element in body with no particular CSS style. When I set .child { margin-top: 10px; } The end result is that top of my child is still aligned with parent. Instead of…
Robert Koritnik
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Nested select statement in SQL Server

Why doesn't the following work? SELECT name FROM (SELECT name FROM agentinformation) I guess my understanding of SQL is wrong, because I would have thought this would return the same thing as SELECT name FROM agentinformation Doesn't the inner…
Brennan Vincent
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How to use a dot "." to access members of dictionary?

How do I make Python dictionary members accessible via a dot "."? For example, instead of writing mydict['val'], I'd like to write mydict.val. Also I'd like to access nested dicts this way. For example mydict.mydict2.val would refer to mydict = {…
bodacydo
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Nested routes with react router v4 / v5

I am currently struggling with nesting routes using react router v4. The closest example was the route config in the React-Router v4 Documentation. I want to split my app in 2 different parts. A frontend and an admin area. I was thinking about…
datoml
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List comprehension on a nested list?

I have this nested list: l = [['40', '20', '10', '30'], ['20', '20', '20', '20', '20', '30', '20'], ['30', '20', '30', '50', '10', '30', '20', '20', '20'], ['100', '100'], ['100', '100', '100', '100', '100'], ['100', '100', '100', '100']] Now, what…
Boy Pasmo
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How to query nested objects?

I have a problem when querying mongoDB with nested objects notation: db.messages.find( { headers : { From: "reservations@marriott.com" } } ).count() 0 db.messages.find( { 'headers.From': "reservations@marriott.com" } ).count() 5 I can't see what I…
Edmondo1984
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Can regular expressions be used to match nested patterns?

Is it possible to write a regular expression that matches a nested pattern that occurs an unknown number of times? For example, can a regular expression match an opening and closing brace when there are an unknown number of open/close braces nested…
Richard Dorman
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Forward declaration of nested types/classes in C++

I recently got stuck in a situation like this: class A { public: typedef struct/class {…} B; … C::D *someField; } class C { public: typedef struct/class {…} D; … A::B *someField; } Usually you can declare a class name: class…
Calmarius
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Why would one use nested classes in C++?

Can someone please point me towards some nice resources for understanding and using nested classes? I have some material like Programming Principles and things like this IBM Knowledge Center - Nested Classes But I'm still having trouble…
bespectacled
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How do you overcome the HTML form nesting limitation?

I know that XHTML doesn't support nested form tags and I have already read other answers here on Stack Overflow regarding this subject, but I still haven't figured out an elegant solution to the problem. Some say you don't need it and that they…
gCoder
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Best way to do nested case statement logic in SQL Server

I'm writing an SQL Query, where a few of the columns returned need to be calculated depending on quite a lot of conditions. I'm currently using nested case statements, but its getting messy. Is there a better (more organised and/or readable) way? (I…
Sophia
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Can you create nested WITH clauses for Common Table Expressions?

WITH y AS ( WITH x AS ( SELECT * FROM MyTable ) SELECT * FROM x ) SELECT * FROM y Does something like this work? I tried it earlier but I couldn't get it to work.
Joe Phillips
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