Rusty things

Rusty things

This page contains some useful information about Rust.

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Run only one test without muting stdout

cargo test -- --nocapture matcher::trie::node::node::given_empty_trie_when_literals_are_inserted_then_they_can_be_looked_up

You need to move out a resource from &mut self

You can do this by destructoring it via a let binding. The destructoring function (like split()) takes self, not a reference. Then it can destructor it.

Reference has a longer lifetime than the data it references

You can extend a lifetime with the following syntax:

struct LiteralLookupHit<'a, 'b: 'a, 'c>(&'a mut Node<'b>, &'c str);

Cannot borrow mutable X multiple times, but there is only one active borrow

Check your lifetimes. If there is one on self it can cause problems. If a trait doesn't need a litetime just one of its methods, then place the lifetime on the method and not on the trait.

Trait implementing a trait

Use case: You have a trait (HasOptionalParameter) which should be implemented by all Parser implementations. At first they would be the same, so you decide to implement HasOptionalParameter for Parser (impl HasOptionalParameter for Parser). With this approach you can get weird compiler errors (type X does not implement any method in scope named Y, but the trait is in scope...).

The solution is to implement HasOptionalParameter for every type which implements Parser:

impl<T> HasOptionalParameter for T where T:Parser { ... }