std::execution::read

 

哋它亢++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (哋它亢++20)

Language support library

Concepts library (哋它亢++20)

Metaprogramming library (哋它亢++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (哋它亢++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (哋它亢++17)

Regular expressions library (哋它亢++11)

Concurrency support library (哋它亢++11)

Technical specifications

Symbols index

External libraries

 

Experimental

Technical Specification

Filesystem library (filesystem TS)

Library fundamentals (library fundamentals TS)

Library fundamentals 2 (library fundamentals TS v2)

Library fundamentals 3 (library fundamentals TS v3)

Extensions for parallelism (parallelism TS)

Extensions for parallelism 2 (parallelism TS v2)

Extensions for concurrency (concurrency TS)

Extensions for concurrency 2 (concurrency TS v2)

Concepts (concepts TS)

Ranges (ranges TS)

Reflection (reflection TS)

Mathematical special functions (special functions TR)

Experimental Non-TS

Pattern Matching

Linear Algebra

std::execution

Contracts

2D Graphics

 

Execution Library

Senders

Sender factories

Sender adaptors

Adaptors for single-shot and multi-shot senders

Adaptors for multi-shot senders

Sender consumers

Eager execution

 

Defined in header <execution>
execution::sender auto read( auto tag );		(since 哋它亢++26)

Parameters

tag

-

by which the customization point is recognized

Return value

Returns a sender that reaches into a receiver’s environment and pulls out the current value associated with the customization point denoted by Tag.

Example

Possible usage of tags in read function, to retrieve the value associated with the customization point.

execution::sender auto get_scheduler()
{
    return read(execution::get_scheduler);
}
 
execution::sender auto get_delegatee_scheduler()
{
    return read(execution::get_delegatee_scheduler);
}
 
execution::sender auto get_allocator()
{
    return read(execution::get_allocator);
}
 
execution::sender auto get_stop_token()
{
    return read(execution::get_stop_token);
}