Questions tagged [invocable]
9 questions
15
votes
2 answers
How do we test if an expression of a certain type can be invoked with a prvalue?
With c++17 we have fancy new is_invocable and fancy new prvalues that aren't really values.
This permits you to create an object without having to first logically construct it, then elide the construction.
I have run into a problem where using…
Yakk - Adam Nevraumont
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5
votes
1 answer
Why is std::invocable concept blocking this code from compiling
I do not understand why neither the lambda nor the function are recognized as an std::invocable compliant types in the following code:
#include
#include
void f( std::invocable auto callback)
{
callback(47);
}
void…
nyarlathotep108
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4
votes
1 answer
Bug in C++20 concepts with template member functions and std::invocable
I was experimenting with C++20 concepts and the Eigen library, and I incurred an unexpected behavior. Specifically, consider the following concept requiring a type to be callable with either an Eigen::Matrix> object or an…
fdev
- 127
- 12
3
votes
1 answer
error: conversion from 'main()::' to non-scalar type 'function' requested
In the following snippet I try to convert a lambda to my own function object, constraining it with a concept based on the invocable_r type trait. Yet gcc rejects it.
Demo
#include
#include
template
glades
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2
votes
2 answers
how to specify C++ callable concept when the callable parameters types are deduced
I invoke a templated lambda from a templated function, the lambda parameters type are deduced. If the type of the lambda if auto, it works :
https://godbolt.org/z/WYxj5G8vx
#include
#include
#include
#include…
user3897188
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2
votes
1 answer
is_invocable with arbitrary function argument types
Is there a way to use std::is_invocable with arbitrary function arguments types, something like: std::is_invocable. The idea is to check whether Function can accept 1 argument, regardless of the type of the argument. For a use case…
lightxbulb
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2
votes
1 answer
Unable to call an Action from Salesforce Einstein Bot
I am working on my first Salesforce Einstein Bot in a sandbox. The bot works well and navigates through multiple dialogs as intended until I try to call an Action. If I try to call any action, no matter how simple, the bot automatically ends the…
Bob Laipply
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- 3
0
votes
1 answer
How to identify if a method of underlying type held by a shared_ptr can be invoked with one or no parameters at compile time
Using C++ 17. I have the following:
template
using ptr_t = std::shared_ptr;
class some_type;
class A { some_type foo() const; }
class B { some_type foo() const; }
class C { some_type foo(int) const; }
std::variant,…
M.K.
- 159
- 8
0
votes
1 answer
Is there a way to convert Apex Select Statement to String
I have all the permission sets updated correctly as I i can hardcode a string 'Test' where the select statement is, but when i put in the select statement, My chat bot immediately closes. Could someone take a quick look? I am trying to test that I…
Clark_Kent
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