mirror of
https://github.com/ETLCPP/etl.git
synced 2026-06-16 00:46:03 +08:00
47 lines
2.1 KiB
Markdown
47 lines
2.1 KiB
Markdown
---
|
|
title: "No STL"
|
|
weight: 2
|
|
---
|
|
|
|
It is possible to use the ETL without any reliance on the STL —
|
|
This can be achieved by defining the project wide macro `ETL_NO_STL`.
|
|
|
|
When this macro is defined then the ETL will used its own reverse engineered versions of traits and algorithms.
|
|
These traits and algorithms are available to the user of the ETL, regardless of whether the STL is used or not.
|
|
|
|
When the STL is used, then, for the most part, the ETL will merely act as a wrapper around the STL definitions.
|
|
|
|
For STL/ETL compatibility, some algorithms and classes in the ETL will use an STL or ETL defined version of a class. For example, if you are using the STL then a function using or returning a pair will use a std::pair.On the other hand, when `ETL_NO_STL` is defined, an `etl::pair` is used.
|
|
|
|
If you wish your code to be able to compiler both with and without the STL, then you would use the `ETL_OR_STD` namespace macro, which resolves to either `std` or `etl`.
|
|
|
|
If the C++ level of your compiler does not support a particular algorithm (e.g. C++03 compiler and `std::sorted_until`), then the ETL will revert to its own version.
|
|
|
|
## Using pair, move, iterator tags or reverse_iterator + others
|
|
When `ETL_NO_STL` is defined then the ETL will use its own versions, otherwise the STL versions will be used. This will affect the return types of certain functions.e.g. `etl::equal_range` will return `ETL_OR_STD::pair` which resolves to either `std::pair` or `etl::pair` ETL types and functions which are not defined in the ETL namespace when the STL is in use :-
|
|
|
|
`pair`
|
|
`make_pair`
|
|
`reverse_iterator`
|
|
`input_iterator_tag`
|
|
`output_iterator_tag`
|
|
`forward_iterator_tag`
|
|
`bidirectional_iterator_tag`
|
|
`random_access_iterator_tag`
|
|
`begin`
|
|
`cbegin`
|
|
`rbegin`
|
|
`crbegin`
|
|
`end`
|
|
`cend`
|
|
`rend`
|
|
`crend`
|
|
`size`
|
|
`swap`
|
|
|
|
## Note
|
|
The ETL is not intended to be a complete clone of the STL.
|
|
The ETL's version of STL features is not exhaustive, and many features are missing.
|
|
|
|
That said, if there is an STL feature missing from the No STL option, then feel free to add it yourself and generate a pull request.
|