An optional argument is an argument which can be omitted, eventually being replaced by a default value, where an argument is an actual value passed to a function, procedure, or command line program.
Questions tagged [optional-arguments]
223 questions
7
votes
3 answers
Typescript: Optional function arguments cause problems in function body
I am new to TypeScript and have a little problem with an optional argument in a function. I got the following error in Visual Studio Code for the query argument (see screen shot). I really don't understand this error, because I defined the type as…
FunkyFabe
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7
votes
1 answer
Can we avoid creating a local variable if an optional argument is not PRESENT?
I am having a problem with the PRESENT statement with Fortran 95. Currently I am using Silverfrost's Plato and their FTN95 compiler (in "Release Win32" mode). What I wanted to do is to create a subroutine SUB(a,b), where b is an optional variable.…
gilbertohasnofb
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7
votes
1 answer
xUnit test engine's InlineDataAttribute + optional method parameters
Is it possible to make xUnit test work when you don't specify optional parameter values in InlineDataAttribute?
Example:
[Theory]
[InlineData(1, true)] // works
[InlineData(2)] // error
void Test(int num, bool fast=true){}
Anri
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6
votes
3 answers
Creating a C# Nullable Int32 within Python (using Python.NET) to call a C# method with an optional int argument
I'm using Python.NET to load a C# Assembly to call C# code from Python. This works pretty cleanly, however I am having an issue calling a method that looks like this:
A method within Our.Namespace.Proj.MyRepo:
OutputObject GetData(string user, int…
skulz00
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5
votes
3 answers
Is there any way to define a Python function with leading optional arguments?
As we know, optional arguments must be at the end of the arguments list, like below:
def func(arg1, arg2, ..., argN=default)
I saw some exceptions in the PyTorch package. For example, we can find this issue in torch.randint. As it is shown, it has a…
javadr
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5
votes
1 answer
Can I define both function's argument's default value and data type in python?
I want to write something like this.
1) def func_name(arg1, arg2, arg3 = 3) #this defines default value for optional argument arg3
2) def func_name(arg1, arg2, arg3: int) #and this defines data type for required argument arg3
Is there any possible…
David Amirkhanyan
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5
votes
1 answer
Complex type as optional argument in web api action
I need to make a complex type parameter optional in 'Web API controller action', so that my action filter for null values can ignore it by checking the argument's property IsOptional. I'm getting this error:
Optional parameter 'errorCode' is not…
Muhammad Saad Javed
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5
votes
2 answers
optional list argument "list = list or []" in python
Conventional way of dealing with optional list arguments is the following:
def func(list_of_vals = None):
if list_of_vals is None:
list_of_vals = []
...
I wounder if the following (shorter) version has any pitfalls? why nobody do that?…
Ben Usman
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5
votes
2 answers
Idiomatic way to make middle arguments optional
What is a common way to implement a JavaScript function whose middle argument(s) are optional, but the last argument is required? An idiomatic ES2015 solution is preferred.
E.g., I commonly see functions that can be invoked in multiple ways, like…
brianmearns
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5
votes
2 answers
How do I use MATLAB's inputParser with optional string inputs? The documentation says "use a validation function" but it's unclear how to do that
I have a MATLAB file that contains a single top-level function, called sandbox. That function in turn contains two nested functions, mysum and myprod, which are identical in functionality and what parameters they allow except that one uses @sum…
Michael A
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5
votes
1 answer
How to specify multiple optional arguments in a function without respecting the order they are given
The below example the optional arguments must be given in order; hence ShowHeaders Must Precede ValueAdd and so on. If I want to specify ValueAdd, I*must* specify ShowHeaders:
Function Example(Value1, Optional ShowHeaders = "Headers=N", Optional…
W A Carnegie
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5
votes
3 answers
error about optional-arguments in common-lisp
SBCL 64bit, 1.1.7
If I want to create a package and use a little symbols from package :CL, I will create a package like this one:
(defpackage :foo
(:import-from :cl
:defun :defmacro :in-package
:null :car :cdr…
xiepan
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4
votes
2 answers
Optional arguments?
Is there a way to declare an argument as "optional" in the Go programming language?
Example of what I mean:
func doSomething(foo string, bar int) bool {
//...
}
I want the parameter bar to be optional and default to 0 if nothing is passed…
thwd
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4
votes
2 answers
How to implement optional arguments in CHICKEN?
I'm new to CHICKEN and Scheme. In my quest to understanding tail recursion, I wrote:
(define (recsum x) (recsum-tail x 0))
(define (recsum-tail x accum)
(if (= x 0)
accum
(recsum-tail (- x 1) (+ x accum))))
This does what I expect it…
cjp
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4
votes
1 answer
Method dispatch with missing arguments
How can I avoid the classic Error: argument "" is missing, with no default error (see example below) when explicitly dispatching argument values to subsequent S4 methods in a given S4 method.
Example
Big picture
Whe have a method foo()…
Rappster
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