A technique for polymorphic invocation of methods based on the types of many (or all) arguments. Compare to single-dispatch, used in common OO languages, where methods can only be polymorphic in the first argument -- the runtime resolution of a.doSomething(x, y, z) depends only on the type of a.
Questions tagged [multiple-dispatch]
106 questions
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Multiple dispatch for return values
I have a routine that can return an array of any FloatingPoint type (or really any numeric type but it's intended for floating points). It computes the convergents of a continued fraction. My problem is that I want the compiler to optimize it for…
Sig TM
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Multiple Dispatch with Generics
I'm trying to abstract away my interface implementations by providing a factory/builder using generics. However, I'm running into an issue with multiple dispatch and C# generics at run time that's doing something that seems odd.
The basic scenario…
SignalRichard
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What is the Julia equivalent to classes and instance variables in Java?
I am trying to avoid repeatedly passing a struct in my functions in order to access its fields. In Java this can be avoided by using a class and defining instance variables. What's the equivalent in Julia?
Here is some sample code where I am…
Brandon
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Use this function if nonlinear expression in vector
I have a vector a that can contain several different types of elements of the expressions QuadExpr, NonlinearExpression, AffExpr, VariableRef. However, I want that if one of the elements (expressions) in a is a NonlinearExpression or a…
Annaquest
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Union type in Julia
I am wondering about types in Julia, more specific Union. For instance, I have made a function where I add the length of my input a into a vector len_a. If a is of type VariableRefI want the length to be 1. I write it like this;
function…
Annaquest
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1 answer
How to overload Base.view() for a custom struct of arrays type in Julia or extend StructArrays type with overloaded base.Push!() method
I should preface this by stating I am very new to the Julia language and I think I am missing something fundamental.
I am trying to setup a numerical simulation code and ultimately want it to work on both CPU and GPU. The method i am attempting is…
Dizzixx
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Is there a 1:1 mapping between static typing and static dispatch vs dynamic typing and dynamic dispatch?
Context: I'm learning Julia and trying to figure out multiple dispatch. I understand the conceptual leap from single dynamic dispatch to multiple dynamic dispatch, but I'm trying to pin down single dynamic dispatch.
Question: Is the following 1:1…
Apples14
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Java vs. Julia: Differences in JIT Compiling and Resulting Performance
I've recently started reading about JIT compilation. On another note, I've read that well-written Julia code often performs on-par with statically compiled languages (see, e.g., paragraph 2 of the introduction section of the Julia docs) while I've…
ruthra
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How to use as a default only one property from a struct?
I want to create a struct with many properties, but when applying the functions, I want it to behave like its type is one of the selected properties, for example:
mutable struct Field{T}
field_type::T
field_description::String
end
I want…
sgaseretto
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Julia identify method by number of keyword arguments
I have two methods with the same name and same amount of "normal" arguments. However, they differ in the number of keyword arguments (which are all non-optional).
I think the following minimal example illustrates my point well:
julia> f(a; b) =…
MetaColon
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Julia: Unpack Arguments from Dictionary or Array for Functions with Multiple Dispatch
My question originated where I had a dictionary of DataFrame values (with compatible columns), and I want to vcat them all together.
Consider how the string function can take any number of string arguments:
string("Fish ", "and ", "chips ") == "Fish…
Owen
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python method overloading - multipledispatch with kwargs
I'm using python3.8 and multipledispatch library in order to overload a method signature.
multipledispatch documentation examples suggests overloading like this:
from multipledispatch import dispatch
@dispatch(int, int)
def add(x, y):
print(x…
Tomer Cohen
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multipledispatch ModuleNotFoundError running from command-line
Running a locust (locust.io) script from the command line.
locust calls main.py which has the following imports:
from locust import HttpUser, between, task
from StreamLoader.stream_generator import * # thought this brings in everything
Packer.py…
Guy
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Multiple Dispatch Swift attempt: Conflicting arguments to generic parameter 'T' ('Cat' vs. 'Dog')
I was watching a video on Julia about Multiple Dispatch and was curious if I could write something similar in Swift. I see that Swift relies on the compiler where Julia seems to determine a type at run time, but I also discovered something I don't…
Turnipdabeets
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Confused about single-dispatch in Java vs multiple dispatch
I’ve read a good post
Just still a little confused about the concept of multiple dispatch (not in Java) vs single dispatch (in Java).
Let’s use this example:
class A {
m(A a) {
System.out.println(“In A: “ + a.getClass());
}
}
class B…
ppp
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