vis_transform.h File Reference

Explicit non-consuming transform adaptor preserving reentrancy. More...

#include "jh/ranges/vis_transform_view.h"

Go to the source code of this file.

Namespaces
namespace	jh::ranges
	Semantic pipeline namespace for JH range operations.
namespace	jh::ranges::views
	Range view adaptor implementations with explicit semantic control.

Variables
constexpr detail::vis_transform_fn	jh::ranges::views::vis_transform {}
	The user-facing vis_transform adaptor.

Detailed Description

Explicit non-consuming transform adaptor preserving reentrancy.

Copyright

Copyright 2025 JeongHan-Bae <mastropseudo@gmail.com>
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

Full license: GitHub

Author

JeongHan-Bae mastr.nosp@m.opse.nosp@m.udo@g.nosp@m.mail.nosp@m..com

The jh::ranges::views::vis_transform adaptor provides an explicit, observation-only variant of std::views::transform. It guarantees non-consuming behavior for reentrant ranges and is used internally by adaptors such as jh::ranges::views::flatten.

Unlike the standard adaptor, which treats every transformation as consumptive, vis_transform ensures that its result remains reentrant and stable whenever the underlying range allows it.

Design rationale

• Non-consuming by contract: The resulting view never consumes its input.
• Explicit intent: Because this guarantees reentrancy, its use must be explicit.
• Interoperability: Fully compatible with jh::ranges::views::common() and jh::ranges::to.

Typical pipeline

A typical usage chain combining multiple adaptors and collection:

auto result = ids
   | jh::ranges::views::enumerate(100)
   | jh::ranges::views::zip_pipe(names)
   | jh::ranges::views::flatten() // invokes vis_transform internally
   | jh::ranges::views::common()
   | jh::ranges::to<std::vector<std::tuple<int, int, std::string>>>();

This form requires no intermediate collect() adaptor — the pipeline remains reentrant, and to<> performs direct construction.

See also

jh::ranges::vis_transform_view

jh::ranges::views::transform

jh::ranges::views::common

jh::ranges::to

Version

1.3.x

Date

2025