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Swap every two elements in a list

Challenge

Let's have a list L of n elements. The task is to swap every two elements in this list.

Constraints

The list L has at least two elements
Size of the list L is a multiple of two (i.e. number of elements is even)

Example

Input: [1,2,3,4,5,6]
Output: [2,1,4,3,6,5]
Input: [0,1,0,1]
Output: [1,0,1,0]

Rules

This is code-golf challenge, so the shortest code wins
Standard rules apply for your answer with default I/O rules, so you are allowed to use stdin/stdout, functions/method with the proper parameters and return-type, full programs
Default Loopholes are forbidden.

Answer*

# [Rust] v1.37.0, <s>59</s> <s>55</s> 47 bytes



 |a:&[_]|(0..).zip(a).map(|i|a[i.0^1]).collect()

[Try it online!][TIO-kvtufp9e]

*-2 bytes thanks to ZippyMagician* 
*-2 bytes thanks to alephalpha* 
*-8 bytes thanks to `(0..).zip(a)`*

Rust is not a golfy language... 
Port of the [C#] and [JS] answers 
v1.37.0 is the version available on TIO

# [Rust] stable, 54 bytes

 |a:&[_]|a.chunks(2).flat_map(|a|[a[1],a[0]]).collect()

[Try it online!](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=303e751fa22451f42bc9f876119481cd)

Thanks to ZippyMagician for this *slightly* golfier answer on the latest version of Rust.

[Rust]: https://www.rust-lang.org/
[C#]: https://codegolf.stackexchange.com/a/237101/44998
[JS]: https://codegolf.stackexchange.com/a/237108/44998
[TIO-kvtufp9e]: https://tio.run/##Lc1NDoIwFATgtZ7iyYK0ybPhR12g4C3cEDQNwaRJKQ2UmEg5e63AajbfzPTjYNxbQcuFIhSm/U42BoYP10PuLM/C8lVZEjFG2VdowilruSZWWF4KFj3jirK6k7KpDaHuuraF0qOBHMoYIUFIEU4IZ4RLtYFuNF5k8Gjqm0iTwtvlkYRLlXqme6GMVAcSTNl9hmMB/wxwHcdtwsvZ/QA "Rust – Try It Online"

If this is an answer to a challenge…

…Be sure to follow the challenge specification. However, please refrain from exploiting obvious loopholes. Answers abusing any of the standard loopholes are considered invalid. If you think a specification is unclear or underspecified, comment on the question instead.
…Try to optimize your score. For instance, answers to code-golf challenges should attempt to be as short as possible. You can always include a readable version of the code in addition to the competitive one. Explanations of your answer make it more interesting to read and are very much encouraged.
…Include a short header which indicates the language(s) of your code and its score, as defined by the challenge.

More generally…

…Please make sure to answer the question and provide sufficient detail.
…Avoid asking for help, clarification or responding to other answers (use comments instead).

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1

\$\begingroup\$ If you don’t use tio's outdated version of rust, |a:&[i32]|a.chunks(2).flat_map(|a|[a[1],a[0]]).collect() is 3 bytes shorter \$\endgroup\$

ZippyMagician
– ZippyMagician

2021年11月11日 01:22:00 +00:00
Commented Nov 11, 2021 at 1:22
\$\begingroup\$ If you do, 57 bytes \$\endgroup\$

ZippyMagician
– ZippyMagician

2021年11月11日 01:24:25 +00:00
Commented Nov 11, 2021 at 1:24
1

\$\begingroup\$ I think you can use &[_] instead of &[i32]. \$\endgroup\$

alephalpha
– alephalpha

2021年11月11日 01:36:31 +00:00
Commented Nov 11, 2021 at 1:36
\$\begingroup\$ @ZippyMagician I managed to outgolf your stable rust answer with TIO's outdated version of rust :P \$\endgroup\$

Mayube
– Mayube

2021年11月18日 17:44:38 +00:00
Commented Nov 18, 2021 at 17:44

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