Named parameters enable you to specify an argument for a particular parameter by associating the argument with the parameter's name rather than with the parameter's position in the parameter list.
Questions tagged [named-parameters]
371 questions
35
votes
4 answers
No named parameters in Ruby?
This is so simple that I can't believe it caught me.
def meth(id, options = "options", scope = "scope")
puts options
end
meth(1, scope = "meh")
-> "meh"
I tend to use hashes for argument options just because it was how the herd did it– and it…
JohnMetta
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35
votes
3 answers
Passing lambda functions as named parameters in C#
Compile this simple program:
class Program
{
static void Foo( Action bar )
{
bar();
}
static void Main( string[] args )
{
Foo( () => Console.WriteLine( "42" ) );
}
}
Nothing strange there. If we make an…
Danko Durbić
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35
votes
12 answers
Named Parameters in Ruby Structs
I'm pretty new to Ruby so apologies if this is an obvious question.
I'd like to use named parameters when instantiating a Struct, i.e. be able to specify which items in the Struct get what values, and default the rest to nil.
For example I want to…
Matt S.
- 9,902
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35
votes
6 answers
C++ "Named Parameter Idiom" vs. Boost::Parameter library
I've looked at both the Named Parameter Idiom and the Boost::Parameter library. What advantages does each one have over the other? Is there a good reason to always choose one over the other, or might each of them be better than the other in some…
Head Geek
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33
votes
6 answers
I want to use named parameters in Dart for clarity. How should I handle them?
TL;DR: Named parameters are optional as a result of a conscious design choice. Short of having official language support, is there any way to enforce (and inform) required named arguments?
I find it extremely useful to use named parameters when…
Kafeaulait
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32
votes
1 answer
How can I force calls to some constructors/functions to use named arguments?
I have some constructors and functions that I'd like to always be called with named arguments. Is there a way to require this?
I'd like to be able to do this for constructors and functions with many parameters and for those that read more clearly…
mfulton26
- 29,956
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31
votes
2 answers
what is the difference between required and @required in flutter. What is the difference between them and when do we need to use them?
If I delete required from the named parameters, it gives me an error:
The parameter 'color' // can't have a value of 'null' because of its
type, but the implicit default value is 'null'.
What is the difference between them and when do we need to…
ulukbek
- 483
- 4
- 10
28
votes
1 answer
named parameters with default values in groovy
Is it possible to have named parameters with default values in groovy? My plan is to make a sort of object factory, which can be called with no arguments at all in order to get an object with default values. Also, I'd need the functionality to…
kaskelotti
- 4,709
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26
votes
10 answers
vsprintf or sprintf with named arguments, or simple template parsing in PHP
I'm searching for a way to use named arguments for sprintf or printf.
Example:
sprintf(
'Last time logged in was %hours hours,
%minutes minutes, %seconds seconds ago'
,$hours,$minutes, $seconds
);
or via vsprintf and an associative array.
I…
Jeremy S.
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26
votes
6 answers
How to call a function with a dictionary that contains more items than the function has parameters?
I am looking for the best way to combine a function with a dictionary that contains more items than the function's inputs
basic **kwarg unpacking fails in this case:
def foo(a,b):
return a + b
d = {'a':1,
'b':2,
'c':3}
foo(**d)
-->…
Len Blokken
- 283
- 2
- 8
25
votes
1 answer
How can I pass named arguments to a Rake task?
Is there a way to pass named arguments to a Rake task without using environment variables?
I am aware that Rake tasks can accept arguments in two formats:
Environment Variables
$ rake my_task foo=bar
This creates an environment variable with the…
Andrew
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24
votes
2 answers
Using named parameters in node.js
I am using node.js v4.3.1
I would like to use named parameters in calling functions as they are more readable.
In python, I can call a function in this manner;
info(spacing=15, width=46)
How do I do the same in node.js?
My javascript function…
guagay_wk
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24
votes
2 answers
Hibernate could not locate named parameter even if it exist
Hibernate Keeps detecting
org.hibernate.QueryParameterException: could not locate named parameter [name]
even though it exist. here's my hql
Query query = sess().createQuery("from UserProfile where firstName LIKE '%:name%'").setParameter("name",…
user962206
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23
votes
3 answers
Why do we need to specify parameter name in interface?
When we create interface methods, can't we do something like in java:
void interface_method(Integer,String, /* other parameter */);
Instead I noticed that we also need to give the parameter names lile:
void interface_method(Integer i, String…
Priyank Doshi
- 12,895
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22
votes
5 answers
Why does Swift require parameter names if it also requires argument order?
In Swift, when you call a function, you are required to label the arguments, unless the author of the function has explicitly allow you not to. Is there a reason for this in terms of language design? I had always viewed parameter labels as a good…
Alex N.
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