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  • If I define a property to prototype appears in the constructor of object, why?

    - by Eduard Florinescu
    I took the example from this question modified a bit: What is the point of the prototype method? function employee(name,jobtitle,born) { this.name=name; this.jobtitle=jobtitle; this.born=born; this.status="single" } employee.prototype.salary=10000000; var fred=new employee("Fred Flintstone","Caveman",1970); console.log(fred.salary); fred.salary=20000; console.log(fred.salary) And the output in console is this: What is the difference salary is in constructor but I still can access it with fred.salary, how can I see if is in constructor from code, status is still employee property how can I tell for example if name is the one of employee or has been touch by initialization? Why is salary in constructor, when name,jobtitle,born where "touched" by employee("Fred Flintstone","Caveman",1970); «constructor»?

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  • Should main method be only consists of object creations and method calls?

    - by crucified soul
    A friend of mine told me that, the best practice is class containing main method should be named Main and only contains main method. Also main method should only parse inputs, create other objects and call other methods. The Main class and main method shouldn't do anything else. Basically what he is saying that class containing main method should be like: public class Main { public static void main(String[] args) { //parse inputs //create other objects //call methods } } Is it the best practice?

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  • Design in "mixed" languages: object oriented design or functional programming?

    - by dema80
    In the past few years, the languages I like to use are becoming more and more "functional". I now use languages that are a sort of "hybrid": C#, F#, Scala. I like to design my application using classes that correspond to the domain objects, and use functional features where this makes coding easier, more coincise and safer (especially when operating on collections or when passing functions). However the two worlds "clash" when coming to design patterns. The specific example I faced recently is the Observer pattern. I want a producer to notify some other code (the "consumers/observers", say a DB storage, a logger, and so on) when an item is created or changed. I initially did it "functionally" like this: producer.foo(item => { updateItemInDb(item); insertLog(item) }) // calls the function passed as argument as an item is processed But I'm now wondering if I should use a more "OO" approach: interface IItemObserver { onNotify(Item) } class DBObserver : IItemObserver ... class LogObserver: IItemObserver ... producer.addObserver(new DBObserver) producer.addObserver(new LogObserver) producer.foo() //calls observer in a loop Which are the pro and con of the two approach? I once heard a FP guru say that design patterns are there only because of the limitations of the language, and that's why there are so few in functional languages. Maybe this could be an example of it? EDIT: In my particular scenario I don't need it, but.. how would you implement removal and addition of "observers" in the functional way? (I.e. how would you implement all the functionalities in the pattern?) Just passing a new function, for example?

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  • How can I explain object-oriented programming to someone who's only coded in Fortran 77?

    - by Zonedabone
    My mother did her college thesis in Fortran, and now (over a decade later) needs to learn c++ for fluids simulations. She is able to understand all of the procedural programming, but no matter how hard I try to explain objects to her, it doesn't stick. (I do a lot of work with Java, so I know how objects work) I think I might be explaining it in too high-level ways, so it isn't really making sense to someone who's never worked with them at all and grew up in the age of purely procedural programming. Is there any simple way I can explain them to her that will help her understand?

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  • Print all values in a value object

    - by SKDev
    I have to debug an issue which requires me to print all the values of a Value Object that is returned by a web service call. The Value object is a complex object in the sense, it has another object as its member which in turn has another object. Printing all the values by using get methods is cumbersome. So was wondering if there is a way to break down the value object by any way to get to a primitive level like String or int or Date and print them all using one API? I had a look at the below question but my prob is that i don't have access to the source code of the value object. The sources are in obfuscated jar. http://stackoverflow.com/questions/2413001/how-to-print-values-of-an-object-in-java

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  • Recommended design pattern for object with optional and modifiable attributtes? [on hold]

    - by Ikuzen
    I've been using the Builder pattern to create objects with a large number of attributes, where most of them are optional. But up until now, I've defined them as final, as recommended by Joshua Block and other authors, and haven't needed to change their values. I am wondering what should I do though if I need a class with a substantial number of optional but non-final (mutable) attributes? My Builder pattern code looks like this: public class Example { //All possible parameters (optional or not) private final int param1; private final int param2; //Builder class public static class Builder { private final int param1; //Required parameters private int param2 = 0; //Optional parameters - initialized to default //Builder constructor public Builder (int param1) { this.param1 = param1; } //Setter-like methods for optional parameters public Builder param2(int value) { param2 = value; return this; } //build() method public Example build() { return new Example(this); } } //Private constructor private Example(Builder builder) { param1 = builder.param1; param2 = builder.param2; } } Can I just remove the final keyword from the declaration to be able to access the attributes externally (through normal setters, for example)? Or is there a creational pattern that allows optional but non-final attributes that would be better suited in this case?

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  • Implement DDD and drawing the line between the an Entity and value object

    - by William
    I am implementing an EMR project. I would like to apply a DDD based approach to the problem. I have identified the "Patient" as being the core object of the system. I understand Patient would be an entity object as well as an aggregrate. I have also identified that every patient must have a "Doctor" and "Medical Records". The medical records would encompass Labs, XRays, Encounter.... I believe those would be entity objects as well. Let us take a Encounter for example. My implementation currently has a few fields as "String" properties, which are the complaint, assessment and plan. The other items necessary for an Encounter are vitals. I have implemented vitals as a value object. Given that it will be necessary to retrieve vitals without haveing to retrieve each Encounter then do vitals become part of the Encounter aggregate and patient aggregrate. I am assuming I could view the Encounter as an aggregrate, because other items are spwaned from the Encounter like prescriptions, lab orders, xrays. Is approach right that I am taking in identifying my entities and aggregates. In the case of vitals, they are specific to a patient, but outside of that there is not any other identity associated with them.

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  • Getting an Error Trying to Create an Object in Python

    - by Nick Rogers
    I am trying to create an object from a class in python but I am getting an Error, "e_tank = EnemyTank() TypeError: 'Group' object is not callable" I am not sure what this means, I have tried Google but I couldn't get a clear answer on what is causing this error. Does anyone understand why I am unable to create an object from my EnemyTank Class? Here is my code: #Image Variables bg = 'bg.jpg' bunk = 'bunker.png' enemytank = 'enemy-tank.png' #Import Pygame Modules import pygame, sys from pygame.locals import * #Initializing the Screen pygame.init() screen = pygame.display.set_mode((640,360), 0, 32) background = pygame.image.load(bg).convert() bunker_x, bunker_y = (160,0) class EnemyTank(pygame.sprite.Sprite): e_tank = pygame.image.load(enemytank).convert_alpha() def __init__(self, startpos): pygame.sprite.Sprite.__init__(self, self.groups) self.pos = startpos self.image = EnemyTank.image self.rect = self.image.get_rect() def update(self): self.rect.center = self.pos class Bunker(pygame.sprite.Sprite): bunker = pygame.image.load(bunk).convert_alpha() def __init__(self, startpos): pygame.spriter.Sprite.__init__(self, self.groups) self.pos = startpos self.image = Bunker.image self.rect = self.image.get_rect() def getCollisionObjects(self, EnemyTank): if (EnemyTank not in self._allgroup, False): return False self._allgroup.remove(EnemyTank) result = pygame.sprite.spritecollide(EnemyTank, self._allgroup, False) self._allgroup.add(EnemyTank) def update(self): self.rect.center = self.pos #Setting Up The Animation x = 0 clock = pygame.time.Clock() speed = 250 allgroup = pygame.sprite.Group() EnemyTank = allgroup Bunker = allgroup e_tank = EnemyTank() bunker = Bunker()5 #Main Loop while True: for event in pygame.event.get(): if event.type == QUIT: pygame.quit() sys.exit() screen.blit(background, (0,0)) screen.blit(bunker, (bunker_x, bunker_y)) screen.blit(e_tank, (x, 0)) pygame.display.flip() #Animation milli = clock.tick() seconds = milli/1000. dm = seconds*speed x += dm if x>640: x=0 #Update the Screen pygame.display.update()

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  • Save Jquery Object without losing its binding

    - by Ahmad Satiri
    Hi I have object created using jquery where each object has it's own binding. function closeButton(oAny){ var div = create_div(); $(div).attr("id","btn_"+$(oAny).attr("id")); var my_parent = this; $(div).html("<img src='"+ my_parent._base_url +"/assets/images/close.gif'>"); $(div).click(function(){ alert("do some action here"); }); return div; } var MyObject = WindowObject(); var btn = closeButton(MyObject); $(myobject).append(btn); $("body").append(myobject); //at this point button will work as i expected //save to array for future use ObjectCollections[0] = myobject; //remove $(myobject).remove(); $(body).append(ObjectCollections[0]); // at this point button will not work For the first time i can show my object and close button is working as i expected. But if i save myobject to any variable for future use. It will loose its binding. Anybody ever try to do this ? Is there any work around ? or It is definitely a bad idea ? .And thanks for answering my question.

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  • Is it possible to restrict instantiation of an object to only one other (parent) object in VB.NET?

    - by Casey
    VB 2008 .NET 3.5 Suppose we have two classes, Order and OrderItem, that represent some type of online ordering system. OrderItem represents a single line item in an Order. One Order can contain multiple OrderItems, in the form of a List(of OrderItem). Public Class Order Public Property MyOrderItems() as List(of OrderItem) End Property End Class It makes sense that an OrderItem should not exist without an Order. In other words, an OrderItem class should not be able to be instantiated on its own, it should be dependent on an Order class to contain it and instantiate it. However, the OrderItem should be public in scope so that it's properties are accessible to other objects. So, the requirements for OrderItem are: Can not be instantiated as a stand alone object; requires Order to exist. Must be public so that any other object can access it's properties/methods through the Order object. e.g. Order.OrderItem(0).ProductID. OrderItem should be able to be passed to other subs/functions that will operate on it. How can I achieve these goals? Is there a better approach?

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  • Adding array to an object breaks the array

    - by DisgruntledGoat
    I have an array like this (output from print_r): Array ( [price] => 700.00 [room_prices] => Array ( [0] => [1] => [2] => [3] => [4] => ) [bills] => Array ( [0] => Gas ) ) I'm running a custom function to convert it to an object. Only the top-level should be converted, the sub-arrays should stay as arrays. The output comes out like this: stdClass Object ( [price] => 700.00 [room_prices] => Array ( [0] => Array ) [bills] => Array ( [0] => Array ) ) Here is my conversion function. All it does is set the value of each array member to an object: function array_to_object( $arr ) { $obj = new stdClass; if ( count($arr) == 0 ) return $obj; foreach ( $arr as $k=>$v ) $obj->$k = $v; return $obj; } I can't figure this out for the life of me!

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  • object / class methods serialized as well?

    - by Mat90
    I know that data members are saved to disk but I was wondering whether object's/class' methods are saved in binary format as well? Because I found some contradictionary info, for example: Ivor Horton: "Class objects contain function members as well as data members, and all the members, both data and functions, have access specifiers; therefore, to record objects in an external file, the information written to the file must contain complete specifications of all the class structures involved." and: Are methods also serialized along with the data members in .NET? Thus: are method's assembly instructions (opcodes and operands) stored to disk as well? Just like a precompiled LIB or DLL? During the DOS ages I used assembly so now and then. As far as I remember from Delphi and the following site (answer by dan04): Are methods also serialized along with the data members in .NET? sizeof(<OBJECT or CLASS>) will give the size of all data members together (no methods/procedures). Also a nice C example is given there with data and members declared in one class/struct but at runtime these methods are separate procedures acting on a struct of data. However, I think that later class/object implementations like Pascal's VMT may be different in memory.

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  • Strange behavior with large Object Types

    - by Peter Lang
    I recognized that calling a method on an Oracle Object Type takes longer when the instance gets bigger. The code below just adds rows to a collection stored in the Object Type and calls the empty dummy-procedure in the loop. Calls are taking longer when more rows are in the collection. When I just remove the call to dummy, performance is much better (the collection still contains the same number of records): Calling dummy: Not calling dummy: 11 0 81 0 158 0 Code to reproduce: Create Type t_tab Is Table Of VARCHAR2(10000); Create Type test_type As Object( tab t_tab, Member Procedure dummy ); Create Type Body test_type As Member Procedure dummy As Begin Null; --# Do nothing End dummy; End; Declare v_test_type test_type := New test_type( New t_tab() ); Procedure run_test As start_time NUMBER := dbms_utility.get_time; Begin For i In 1 .. 200 Loop v_test_Type.tab.Extend; v_test_Type.tab(v_test_Type.tab.Last) := Lpad(' ', 10000); v_test_Type.dummy(); --# Removed this line in second test End Loop; dbms_output.put_line( dbms_utility.get_time - start_time ); End run_test; Begin run_test; run_test; run_test; End; I tried with both 10g and 11g. Can anyone explain/reproduce this behavior?

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  • How to Object Array to List

    - by Peter Black
    (C#) I have 2 classes. 1 is called Employee. The other is my "main". I am trying to take a list and assign each value in list to an array of Employee object. //Inside "Main" class int counter = NameList.Count; Employee[] employee = new Employee[counter]; for (int i = 0; i <= counter; i++) { employee[i].Name = NameList[i]; employee[i].EmpNumber = EmpNumList[i]; employee[i].DateOfHire = DOHList[i]; employee[i].Salary = SalaryList[i]; employee[i].JobDescription = JobDescList[i]; employee[i].Department = DeptList[i]; } This returns the error: An unhandled exception of type 'System.NullReferenceException' occurred in Pgm4.exe Additional information: Object reference not set to an instance of an object. I think this means that I am not calling the list properly. Any help would be much appreciated. Thank you.

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  • java /TableModel of Objects/Update Object"

    - by Tomás Ó Briain
    I've a collection of Stock objects that I'm updating about 10/15 variables for in real-time. I'm accessing each Stock by its ID in the collection. I'm also trying to display this in a JTable and have implemented an AbstractTablemodel. It's not working too well. I've a RowMap that I add each ID to as Stocks are added to the TableModel. To update the prices and variables of all the stocks in the TableModel, I want to send a Stock object to an updateModel(Stock s) method. I can find the relevant row by searching the map, but how do I handle this nicely, so I don't have to start iterating through table columns and comparing the values of the cells to the variables of the object to see whether there are any differences?? Basically, i want to send a Stock object to the TableModel and update cells if there are changes and do nothing if there aren't. Any ideas about how to implement a TableModel that might do this? Any pointeres at all would be appreciated. Thanks.

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  • How to create PHP method linking?

    - by Kerry
    I've seen other objects that do this: $obj->method1()->method2(); How do I do that? Is each function just modifying the pointer of an object or returning a pointer? I don't know the proper term for this style -- if anyone could help me with that, it would be great.

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  • Object value not getting updated in the database using hibernate

    - by user1662917
    I am using Spring,hibernate,jsf with jquery in my application. I am inserting a Question object in the database through the hibernate save query . The question object contains id ,question,answertype and reference to a form object using form_id. Now I want to alter the values of Question object stored in the database by altering the value stored in the list of Question objects at the specified index position. If I alter the value in the list the value in the database is not getting altered by update query . Could you please advise. Question.java package com.otv.model; import java.io.Serializable; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.JoinColumn; import javax.persistence.ManyToOne; import javax.persistence.Table; import org.apache.commons.lang.builder.ToStringBuilder; @Entity @Table(name = "questions") public class Question implements Serializable { @Id @GeneratedValue @Column(name = "id", unique = true, nullable = false) private int id; @Column(name = "question", nullable = false) private String text; @Column(name = "answertype", nullable = false) private String answertype; @ManyToOne(fetch = FetchType.EAGER) @JoinColumn(name = "form_id") private Form form; // @JoinColumn(name = "form_id") // private int formId; public Question() { } public Question(String text, String answertype) { this.text = text; this.answertype = answertype; } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getQuestion() { return text; } public void setQuestion(String question) { this.text = question; } public String getAnswertype() { return answertype; } public void setAnswertype(String answertype) { this.answertype = answertype; } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + ((answertype == null) ? 0 : answertype.hashCode()); result = prime * result + id; result = prime * result + ((text == null) ? 0 : text.hashCode()); return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Question other = (Question) obj; if (answertype == null) { if (other.answertype != null) return false; } else if (!answertype.equals(other.answertype)) return false; if (id != other.id) return false; if (text == null) { if (other.text != null) return false; } else if (!text.equals(other.text)) return false; return true; } public void setForm(Form form) { this.form = form; } @Override public String toString() { return ToStringBuilder.reflectionToString(this); } } Form.java package com.otv.model; import java.io.Serializable; import java.util.ArrayList; import java.util.List; import javax.persistence.CascadeType; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.OneToMany; import javax.persistence.Table; import org.apache.commons.lang.builder.ToStringBuilder; @Entity @Table(name = "FORM") public class Form implements Serializable { @Id @GeneratedValue @Column(name = "id", unique = true, nullable = false) private int id; @Column(name = "name", nullable = false) private String name; @Column(name = "description", nullable = false) private String description; @OneToMany(mappedBy = "form", fetch = FetchType.EAGER, cascade = CascadeType.ALL) List<Question> questions = new ArrayList<Question>(); public Form(String name) { super(); this.name = name; } public Form() { super(); } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getDescription() { return description; } public void setDescription(String description) { this.description = description; } public List<Question> getQuestions() { return questions; } public void setQuestions(List<Question> formQuestions) { this.questions = formQuestions; } public void addQuestion(Question question) { questions.add(question); question.setForm(this); } public void removeQuestion(Question question) { questions.remove(question); question.setForm(this); } @Override public String toString() { return ToStringBuilder.reflectionToString(this); } public void replaceQuestion(int index, Question question) { Question prevQuestion = questions.get(index); // prevQuestion.setQuestion(question.getQuestion()); // prevQuestion.setAnswertype(question.getAnswertype()); question.setId(prevQuestion.getId()); question.setForm(this); questions.set(index, question); } } QuestionDAO.java package com.otv.user.dao; import java.util.List; import org.hibernate.SessionFactory; import com.otv.model.Question; public class QuestionDAO implements IQuestionDAO { private SessionFactory sessionFactory; public SessionFactory getSessionFactory() { return sessionFactory; } public void setSessionFactory(SessionFactory sessionFactory) { this.sessionFactory = sessionFactory; } public void addQuestion(Question question) { getSessionFactory().getCurrentSession().save(question); } public void deleteQuestion(Question question) { getSessionFactory().getCurrentSession().delete(question); } public void updateQuestion(Question question) { getSessionFactory().getCurrentSession().update(question); } public Question getQuestionById(int id) { List list = getSessionFactory().getCurrentSession().createQuery("from Questions where id=?") .setParameter(0, id).list(); return (Question) list.get(0); } }

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  • Ongoing confusion about ivars and properties in objective C

    - by Earl Grey
    After almost 8 months being in ios programming, I am again confused about the right approach. Maybe it is not the language but some OOP principle I am confused about. I don't know.. I was trying C# a few years back. There were fields (private variables, private data in an object), there were getters and setters (methods which exposed something to the world) ,and properties which was THE exposed thing. I liked the elegance of the solution, for example there could be a class that would have a property called DailyRevenue...a float...but there was no private variable called dailyRevenue, there was only a field - an array of single transaction revenues...and the getter for DailyRevenue property calculated the revenue transparently. If somehow the internals of daily revenue calculation would change, it would not affect somebody who consumed my DailyRevenue property in any way, since he would be shielded from getter implementation. I understood that sometimes there was , and sometimes there wasn't a 1-1 relationship between fields and properties. depending on the requirements. It seemed ok in my opinion. And that properties are THE way to acces the data in object. I know the difference betweeen private, protected, and public keyword. Now lets get to objectiveC. On what factor should I base my decision about making someting only an ivar or making it as a property? Is the mental model the same as I describe above? I know that ivars are "protected" by default, not "private" asi in c#..But thats ok I think, no big deal for my presnet level of understanding the whole ios development. The point is ivars are not accesible from outside (given i don't make them public..but i won't). The thing that clouds my clear understanding is that I can have IBOutlets from ivars. Why am I seeing internal object data in the UI? *Why is it ok?* On the other hand, if I make an IBOutlet from property, and I do not make it readonly, anybody can change it. Is this ok too? Let's say I have a ParseManager object. This object would use a built in Foundation framework class called NSXMLParser. Obviously my ParseManager will utilize this nsxmlparser's capabilities but will also do some additional work. Now my question is, who should initialize this NSXMLParser object and in which way should I make a reference to it from the ParseManager object, when there is a need to parse something. A) the ParseManager -1) in its default init method (possible here ivar - or - ivar+ppty) -2) with lazyloading in getter (required a ppty here) B) Some other object - who will pass a reference to NSXMLParser object to the ParseManager object. -1) in some custom initializer (initWithParser:(NSXMLPArser *) parser) when creating the ParseManager object.. A1 - the problem is, we create a parser and waste memory while it is not yet needed. However, we can be sure that all methods that are part ot ParserManager object, can use the ivar safely, since it exists. A2 - the problem is, the nsxmlparser is exposed to outside world, although it could be read only. Would we want a parser to be exposed in some scenario? B1 - this could maybe be useful when we would want to use more types of parsers..i dont know... I understand that architectural requirements and and language is not the same. But clearly the two are in relation. How to get out of that mess of my? Please bear with me, I wasn't able to come up with a single ultimate question. And secondly, it's better to not scare me with some superadvanced newspeak that talks about some crazy internals (what the compiler does) and edge cases.

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  • How to pass object from one activity to another in android

    - by kaibuki
    Hi I am trying to work on sending an object of my "Customer" class from one activity and display on other activity. the code for the customer class : `package com.kaibuki; public class Customer { private String firstName, lastName, Address; int Age; public Customer(String fname, String lname, int age, String address) { firstName = fname; lastName = lname; Age = age; Address = address; } public String printValues() { String data = null; data = "First Name :" + firstName + " Last Name :" + lastName + " Age : " + Age + " Address : " + Address; return data; } } I want to send its object from one activity to another and then display the data on the other activity. Please need urgent help. Thanks alot Kai`

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  • Is learning the Caché database hard coming from relational databases and object oriented programming

    - by Edelcom
    I am currently running the local version of Caché on my system in order to determine if I can (and will) take on a new possible project. The current project uses Delphi 7 as a front end calling a Caché dll where the business logic is stored in the database. I have a background of Sqlserver and Firebird (and before Access and Paradox) as databases. I use Delphi 7 for 95% of my Windows development, so I know about object programming. I would like to recieve opinions from persons having used Caché and either SqlServer, Firebird or Oracle and having developed in Delphi (or C++ or C# - an object oriented language). I have read the pro's and con's from other questions, but I am not asking for this, I need input from Caché developers. Thanks in advance.

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  • PHP intersection between array and object

    - by nickf
    I have an object, let's say it's like this: class Foo { var $b, $a, $r; function __construct($B, $A, $R) { $this->b = $B; $this->a = $A; $this->r = $R; } } $f = new Foo(1, 2, 3); I want to get an arbitrary slice of this object's properties as an array. $desiredProperties = array('b', 'r'); $output = magicHere($foo, $desiredProperties); print_r($output); // array( // "b" => 1, // "r" => 3 // )

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  • Rails: Object#id will be deprecated; use Object#object_id

    - by sscirrus
    Hi everyone, Very quick question. My server is warning me that line 37 will be deprecated, specifically: #Server error: views/projects/index.html.erb:37: warning: Object#id will be deprecated; use Object#object_id #Views/projects/index.html.erb: 6: <% for project in @projects do %> 36: <%= project.id %> 37: <%= Matching.find_all_by_customer_id_and_project_id( @customer.id, project.id).id %> 38: <%= @customer.id %> Here's my confusion. Line 36 project.id isn't raising a warning, so I assume the issue is that I'm calling ID on the Matching model. Why is it the case that only Matching raising an error and not customer or project? How can I rectify this in my code? Thanks very much.

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  • python duration of a file object in an argument list

    - by msw
    In the pickle module documentation there is a snippet of example code: reader = pickle.load(open('save.p', 'rb')) which upon first read looked like it would allocate a system file descriptor, read its contents and then "leak" the open descriptor for there isn't any handle accessible to call close() upon. This got me wondering if there was any hidden magic that takes care of this case. Diving into the source, I found in Modules/_fileio.c that file descriptors are closed by the fileio_dealloc() destructor which led to the real question. What is the duration of the file object returned by the example code above? After that statement executes does the object indeed become unreferenced and therefore will the fd be subject to a real close(2) call at some future garbage collection sweep? If so, is the example line good practice, or should one not count on the fd being released thus risking kernel per-process descriptor table exhaustion?

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