Function is a block of code which performs a specific task.
5
votes
2answers
182 views
Boolean Method Naming Affirmative vs Negative
Should boolean methods always take the affirmative form, even when they will only ever be used in the negative form?
Say I wanted to check whether an entity exists before creating one, my argument is ...
1
vote
1answer
105 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
2answers
132 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 ...
80
votes
13answers
18k views
Is it OK to split long functions and methods into smaller ones even though they won't be called by anything else?
Lately I've been trying to split long methods into several short ones.
For example: I have a process_url() function which splits URLs into components and then assigns them to some objects via their ...
-2
votes
0answers
96 views
Please tell me the output of this C program and also explain how it comes? [closed]
void xyz(int x)
{
printf("\n%d",x);
if(x)
xyz(x-1)
printf("\n%d",x);
}
void abc(int a)
{
printf("\n%d",a);
xyz(a);
if(a)
abc(a-1);
printf("\n%d",a);
}
void main()
{
abc(2);
}
0
votes
0answers
6 views
Comparing two functions in JavaScript [migrated]
I'm developing a mobile app for my wife's 1st grade class so they can practice sight words. I'm a novice to JavaScript but I was able to pull off my first objective which was to take a JavaScript ...
8
votes
4answers
580 views
C++ why & how are virtual functions slower?
Can anyone explain in detail, how exactly the virtual table works & what pointers are associated when virtual functions are called. If they are actually slower, can you show the time that the ...
-1
votes
1answer
116 views
max(x-y,0) is loop-computable [closed]
I use the programming language Loop: http://en.wikipedia.org/wiki/LOOP_%28programming_language%29
I know that the every primitve recursive function is loop computable and vice versa but I would like ...
1
vote
3answers
137 views
CoffeeScript and Named Functions
Elsewhere: an argument has arisen over the terminology of a named function in CoffeeScript. In particular somebody refereed to something like this
foo = ->
console.log("bar")
as a named ...
1
vote
1answer
107 views
LOOP program only need inc and zero
I have 4 different commands in LOOP programming language:
y=Zero()
y=Val(x)=copy x and put it in register y
y=Inc(x)=x+1
y=Dec(x)=x-1
Finally I also have
loop n times {
...
...
2
votes
1answer
128 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 ...
4
votes
3answers
273 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 ...
5
votes
5answers
493 views
Why Java does not allow function definitions to be present outside of the class?
Unlike C++, in Java, we cannot have just function declarations in the class and definitions outside of the class. Why is it so?
Is it to emphasize that a single file in Java should contain only one ...
38
votes
9answers
3k views
Why is Today() an example of an impure function?
It seems like, when reading something like this Wikipedia article about "pure functions", they list Today() as an example of an impure function but it seems pretty pure to me. Is it because there is ...
4
votes
2answers
404 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 ...
18
votes
2answers
899 views
Is it a good idea to provide different function signatures that do the same thing?
Here is a C++ class that gets constructed with three values.
class Foo{
//Constructor
Foo(std::string, int, char);
private:
std::string foo;
char bar;
int baz;
};
All of ...
0
votes
1answer
749 views
Drawing Flowchart for function calculate a number in the Fibonacci Series
I'm trying make Flowchart for function calculate a number in the Fibonacci Series. But It looks like not right. I don't how draw the recursive function.
Please help me how to fix it.
My flowchart: ...
11
votes
4answers
533 views
Why store a function inside a python dictionary?
I'm a python beginner, and I just learned a technique involving dictionaries and functions. The syntax is easy and it seems like a trivial thing, but my python senses are tingling. Something tells me ...
3
votes
1answer
106 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 ...
7
votes
3answers
418 views
Why can't we write nested shorthand functions in Clojure?
I tried to evaluate a Clojure expression with nested shorthand functions today, and it wouldn't let me.
The expression was:
(#(+ % (#(+ % (* % %)) %)) 5) ; sorry for the eye bleed
The output was:
...
2
votes
1answer
124 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 ...
0
votes
1answer
111 views
The idea of functionN in Scala / Functionaljava
From brain driven development
It turns out, that every Function you’ll ever define in Scala, will
become an instance of an Implementation which will feature a certain
Function Trait.
...
0
votes
2answers
64 views
Looking for terminology for the relation of a subject and a predicate
While writing some predicates for collection filtering I have stumbled over the choice of the right words for the relation of the subject and the predicate (English is a foreign language for me). What ...
6
votes
3answers
264 views
Functional Methods on Collections
I'm learning Scala and am a little bewildered by all the methods (higher-order functions) available on the collections. Which ones produce more results than the original collection, which ones ...
10
votes
1answer
329 views
Is there a difference between arguments and parameters?
It might be like this: Parameter means from the callers POV and arguments mean inside the procedure, or other way round.
Or is there no difference?
Update
In Swedish we say "anropsparametrar" i.e. ...
5
votes
2answers
327 views
What can procs and lambdas do that functions can't in ruby
I've been working in Ruby for the last couple weeks, and I've come to the subject of procs, lambdas and blocks. After reading a fair share of examples from a variety of sources, I don't how they're ...
5
votes
2answers
471 views
Is it bad practice to output from within a function?
For example, should I be doing something like:
<?php
function output_message($message,$type='success') {
?>
<p class="<?php echo $type; ?>"><?php echo $message; ...
4
votes
2answers
364 views
Function that requires many parameters
I have a problem related to this:
Are there guidelines on how many parameters a function should accept?
In my case, I have a function that describes a rounded rectangle. The caller specifies
An ...
4
votes
4answers
328 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 ...
11
votes
4answers
907 views
Function declaration as var instead of function
More and more I'm seeing functions being declared like
var foo = function() {
// things
};
Instead of how I had learned, like
function foo() {
// things
}
What's the difference? Better ...
13
votes
1answer
550 views
Why does the C library use macros and functions with same name?
I am reading 'The Standard C Library' by PJ Plauger which is really interesting. The book explains not only how to USE the library but also how it is implemented.
I have finished reading the ctype.h ...
3
votes
5answers
311 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.
...
3
votes
3answers
328 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 ...
11
votes
5answers
228 views
Convert list of 24-hour-precipitation values into total-by-hour
Let's say I have a list of precipitation values by hour, each showing how much rain happened in the prior 24 hours, ordered by date. For example:
{
'2012-05-24 12:00': 0.5, // .5" of rain from ...
6
votes
4answers
1k views
What is the name for a NON-self-calling function?
I have a collection of normal functions and self-calling functions within a javascript file. In my comments i want to say something along the lines of "This script can contain both self-calling and ...
1
vote
3answers
458 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 ...
22
votes
9answers
2k views
Are there guidelines on how many parameters a function should accept?
I've noticed a few functions I work with have 6 or more parameters, whereas in most libraries I use it is rare to find a function that takes more than 3.
Often a lot of these extra parameters are ...
-5
votes
5answers
1k views
Function like C# properties?
I've been thinking about how C# properties work and could work.
I know the purpose that C# properties were originally designed for, which is certainly useful. However instead in this question I'm ...
0
votes
1answer
110 views
Using functions as statements on Python
A great feature of Javascript is function statements. You can do this:
(function myFunc(){
doSomething();
doSomethingElse();
})();
Which is a way to declare a function and call it without ...
4
votes
5answers
290 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 ...
9
votes
3answers
2k views
Where should I put functions that are not related to a class?
I am working on a C++ project where I have a bunch of math functions that I initially wrote to use as part of a class. As I've been writing more code, though, I've realized I need these math functions ...
2
votes
2answers
511 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 ...
2
votes
2answers
159 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 ...
3
votes
2answers
249 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
5answers
471 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 ...
74
votes
10answers
4k views
One-line functions that are called only once
Consider a parameterless (edit: not necessarily) function that performs a single line of code, and is called only once in the program (though it is not impossible that it'll be needed again in the ...
5
votes
4answers
735 views
When would dynamic scoping be useful?
With dynamic scoping, a callee can access the variables of its caller. Pseudo C code:
void foo()
{
print(x);
}
void bar()
{
int x = 42;
foo();
}
Since I have never programmed in a ...
3
votes
2answers
300 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 ...
8
votes
6answers
2k views
Feature vs. Function
Often I hear PMs (Project Managers) talk about feature and function. And I'm just so puzzled to differentiate them. Sometimes I think of a feature to be equivalent to a user story. Something like "As ...
3
votes
8answers
358 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 ...
