Added Send+Sync to MutableBuffer

[jorgecarleitao]

No description provided.

[codecov]

Codecov Report

Merging #368 (ec1462f) into main (cef5f08) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #368   +/-   ##
=======================================
  Coverage   81.05%   81.05%           
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  Files         326      326           
  Lines       21103    21103           
=======================================
  Hits        17105    17105           
  Misses       3998     3998           

Impacted Files	Coverage Δ
src/buffer/mutable.rs	88.29% <ø> (ø)

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[sundy-li]

Why MutableBuffer is Sync? There are lots of methods inside that are not sync.

I get it now.

[jorgecarleitao]

Why MutableBuffer is Sync? There are lots of methods inside that are not sync.

Implementing Sync means that a type guarantees that references to its values can be shared between threads, without risk of a data race in safe Rust.

Values of type &MutableBuffer<T> are immutable and it is thus safe to share them.

In essence, it is the same reason why Vec<T> is Sync iff T is Sync.