Function is a block of code which performs a specific task.

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4
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8answers
526 views

Confusion regarding def function within Python

I've been learning Python for about 2 months now (Started with Learn Python The Hard Way, now reading Dive Into Python), and within both books, I still seem to be confused over this one bit of code. ...
4
votes
3answers
419 views

Renaming long named method in C# [closed]

I'm working on a project where exist one method with title string ValidateNewPasswordExpireCurrentPasswordAndCreateNewPassword(...) I'm sure the method name must be changed. But can't found good ...
4
votes
2answers
991 views

How can “hash functions” be used to implement hash maps at all?

My understandment is that hash maps allow us to link, say, a string, to certain memory location. But if every string were to be linked to a unique place in memory it would need a huge block of empty ...
4
votes
5answers
694 views

Using php functions, reserved words as local identifiers [closed]

I'm thinking of some of the array functions. "key", "each", "pos", "range". These are often very useful as local identifiers! I have also seen code that (ab)uses $return, $list, $array, $string. What ...
4
votes
2answers
1k views

Why are there no function pointers in Java? [closed]

Lately I started studying about different interesting concepts that exist in languages other than Java. Since the only language I've ever programmed with is Java, a lot of these concepts are very new ...
4
votes
2answers
682 views

Should I put utility methods inside a class?

I have been working on a library which contains a large set of functions. For the sake of simplicity, I am going to use just one set as an example. I am not sure which is the better way, in terms of ...
4
votes
4answers
2k views

Best Method of function parameter validation

I've been dabbling with the idea of creating my own CMS for the experience and because it would be fun to run my website off my own code base. One of the decisions I keep coming back to is how best ...
3
votes
8answers
488 views

Wrapping simple statement in a function in java?

I was working on neo4j graph database in java. To get the reference node of this db: GraphDatabaseService graphDb=new EmbeddedGraphDatabase(DB_PATH); Node Root=graphDb.getReferenceNode() I ...
3
votes
2answers
303 views

Should I use chained functions in Java?

From time to time, I'll have a class in Java that takes a multitude of parameters, however, sometimes when I am creating an object of this class, I don't need to use all the parameters. As of now, I ...
3
votes
3answers
445 views

Good Procedure or Function Design

This is in reference to the question posted here. As I would judge it, the question there should be closed simply because it seems to ask why the Borland developers made one thing a function and ...
3
votes
3answers
400 views

How are functions called when passing ++

I don't understand what is passed to the function f() when I call it like this. main() { void f(int,int); int i=10; f(i,i++); } void f(int i,int j) { printf("%d %d",i,j); } gives me 11 10 ...
3
votes
3answers
292 views

When is inlining worth it?

Modern compilers often inline functions when they decide it is worth it. But here comes my question: how does one define if it is optimal to inline function at given time, or more important how to ...
3
votes
5answers
2k views

Template Functions and Function templates in C++

I came across a question which asked the difference between Function Templates and Template Functions in C++ and also Template Classes and Class Templates. I was under the impression that Function ...
3
votes
4answers
1k views

Is function memoization really only for primitives?

I was thinking about this for quite some time. Is function memoization really only for primitives? I currently have this piece of code: Public Shared Function Mize(Of TArg1 As Structure, ...
3
votes
2answers
108 views

Strategies for parameter wrapping

Methods with many parameters are often sometimes unavoidable. In my own experience I often find this is the case for program entry points and complex mathematical procedures - where refactoring is ...
3
votes
5answers
1k views

Functions with side-effects in Delphi/Pascal

What is the proper approach to functions that have side-effects in Delphi/Pascal? For example, I could have a boolean function DeleteFile that returns True if the file was deleted and False ...
3
votes
4answers
411 views

int * vs int [N] vs int (*)[N] in functions parameters. Which one do you think is better?

When programming in C (or C++) there are three different ways to specify the parameter in a function that takes an array. Here is an example (implementing std::accumulate from C++ in C) that shows ...
3
votes
2answers
553 views

Programming by Intention, Depth-First or Breadth-First?

Say I have the following graph of dependencies between procedures/functions/methods: o / \ v e / \ / \ r f l w That is, function o first calls function v, and then ...
3
votes
2answers
2k views

Setting $_POST variables as a means of passing data / Not passing parameters in functions

I've got a legacy PHP web application wherein almost each and every function makes references to $_POST variables - retrieving their values, AND setting them (or setting new POST variables) as a means ...
3
votes
3answers
1k views

Call stack starts at bottom or top?

A stack is something that piles bottom-up. Hence a call stack adds new items on the stack when functions are called with items being removed from the stack as each function ends until the stack is ...
3
votes
1answer
186 views

Returning status code where one of many errors could have occured

I'm developing a PHP login component which includes functions to manipulate the User object, such as $User->changePassword(string $old, string $new) What I need some advice with is how to return a ...
2
votes
5answers
584 views

When, if ever, should I daisy chain functions?

I'll try to be as brief as possible in respect to your time. In a program divided up into many functions by which it is intended that they execute themselves one after another, when (if ever) is it ...
2
votes
4answers
370 views

How do you decide what code to put into a function?

I started out with a script that was a few hundred lines. Later, I realized I wanted another script that would require much of the same code. I decided to wrap certain areas of the original script ...
2
votes
3answers
160 views

Non-trivial get function, should it be named differently

For example I have this code. class Command { var $responseFactory; var $service; /** * Returns the class name of the responseFactory if it is set * or the default class name ...
2
votes
1answer
320 views

How do multiple levels of inheritance affect virtual function call overhead in C++?

I am considering using a class hierarchy with more than a single level of inheritance, where virtual member functions form a "chain", for example: struct Base { virtual void foo(); }; struct D1 : ...
2
votes
2answers
166 views

Property or Method to obtain information about a collection?

Suppose I have a MyList class which extends ObservableCollection<MyObject> where MyObject has the Boolean Property Enabled. Let's say I want the number of MyObject objects that have the ...
2
votes
3answers
301 views

Does designing a method that changes the argument's (if was object) values a good practice?

The premise is using a language (e.g. C#, javascript) which passes an object by reference into a method. Assume there is an object "Player" which has a property "Level" and there is a method takes ...
2
votes
4answers
109 views

To make a class function or not?

I'm wondering about functions used like this: object1->objectMethod1(arg1, arg2); if objectMethod1: - does not change the object state - does not use the object's state at all - is used by the ...
2
votes
1answer
143 views

Does automatic returning affect performance?

There's a bunch of languages that automatically return the last value in a function (mostly functional) like Ruby, Haskell, Lisp, etc. Does this feature (or what do you call it) affect the ...
2
votes
3answers
235 views

Using past participle for non-altering functions [closed]

I often have naming problems when I write classes and functions. Generally speaking, I try to follow the following set of rules if I have to deal with a function whose name is a verb: If the ...
2
votes
2answers
558 views

Why function returning by Address can not be a Lvalue?

Why it is not possible to make it LValue if a function return by address (while possible in case of reference)? int* returnByAdress() { int x =20; return &x; } int& ...
2
votes
2answers
1k views

What is Module Object and Function Object?

I am currently teaching myself Python, using the GNU licensed book "Introduction to Computer Science using Python." In chapter 3, functions are covered. While I understand the concept of functions ...
2
votes
1answer
109 views

How to simplify unit testing with higher order functions?

this is not a question on how to write unit tests this is not a question on what to test this is a question on reducing the typing needed overall for a personal testing framework I know you can ...
2
votes
1answer
159 views

LOOP-computable functions

I was just reading a chapter about LOOP-computable functions and I have the following question: Is it possible to numerate every LOOP program with an algorithm? Formally: Is it possible to have a ...
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3answers
332 views

How are basic functions implemented in a programming language if they are not built in? [closed]

The lowest levels of a programming language's library functions are always obscure and often have no code that looks like it even remotely does anything. Some languages have these functions like ...
1
vote
6answers
492 views

Naming functions that retrieve a value

I have this personal rule to start all function/method names with a verb. My verb of choice for functions or methods that get a value based on some data structure or object is get. I'm wondering if ...
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vote
2answers
252 views

Using Functions for Never-Repeated Code [duplicate]

What are some best practices for using functions to break up large blocks of code into discrete chunks of logic when those functions are only ever going to be used once within the lifetime of a ...
1
vote
2answers
217 views

Are any side effects not concrete side effects?

In Chapter 23 of "Object Oriented Software Construction" (1988), Betrand Meyer makes a distinction between side effects, concrete side effects, and abstract side effects. Meyer defines a side effect ...
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2answers
47 views

Function that would output all distinct values in an array

I want to create a function that outputs the distinct values in a given array. For example, in the following sequence 2 2 1 1 5 2 , the distinct digits are 2 1 5. What I've done till now is: void ...
1
vote
2answers
163 views

How does the CPU access the values of stack-allocated variables? [duplicate]

Consider the following C++ function: void doStuff() { Thing thingA; Thing thingB; thingA.doSomething(); // .. etc } During the execution of this function, variables thingA and ...
1
vote
6answers
883 views

An alternative to an array of functions?

I'm programming an app (php) which requires a very long list of similar yet different functions, which are being called by a set of keys: $functions = [ "do this" => function() { // ...
1
vote
1answer
163 views

Documenting Function That Takes Random Parameters?

What's the best approach to creating documentation (displaying the function prototype if you will) for functions that take a variety of different forms in terms of parameters. Let's say there are 10 ...
1
vote
1answer
71 views

When should one create a new py-function rather than tweaking another one?

Me and a co-developer are arguing when it's wise to cast a new function rather than tweaking another one. By tweaking I mean an option or a hidden check in an existing function. The question could be ...
1
vote
1answer
65 views

Are there defined standards for argument sequence? [closed]

Say I have a function taking three arguments: a symbol (an alias for a class, method or function name) a mirror/reflection of a specific object a mirror/reflection of a class in general is there a ...
1
vote
3answers
197 views

Reason to treat internal class variables and functions inside a class as “separate” entities

Note: there is a similar question that addresses my subject: Better style for member variables? ... but that question does not address "dealing with large legacy code base and comprehension of ...
1
vote
3answers
3k views

If statements vs switch cases? in a JavaScript game and if to use a function [duplicate]

I am developing a game in JavaScript where you start with a user input, stored in the variable "controller". The options for the user consists of start to start the game or about to learn about the ...
1
vote
2answers
185 views

What is the concept behind writing a cancel operation in c++? [closed]

I'm attempting to write a cancel operation for a software download application. This application will first transfer the software to the device and then install the software on it. (These are givens ...
1
vote
1answer
132 views

Helper functions - well defined inputs or well defined outputs?

Problem In Codeigniter (PHP framework), I am trying to create a helper function that will inject an ActiveRecord (for MySQL) command into a chain of existing ActiveRecord calls. The reasoning for ...
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1answer
124 views

Use Generic of Specific Function names for similar objects

Is there a school of thought on putting focus on using generic names for functions, opposed to naming functions based on the things they do? Example Say we have a Bill / Price Sheet object, that has ...
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vote
0answers
16 views

Hidden event handlers and their parameters

I'm having a bit of trouble understanding why has an event handler to be defined as a function. AFAIK, a function can be used as anonymous called procedure as event handler It defines a ...