Use references for scalar operands

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
rust
Domain
data

Research direction

Start by tracing the ops macros and the ScalarOperand and StaticOperand implementations mentioned in the issue, then reproduce the array-plus-referenced-scalar example. Investigate the conflicting implementation error and existing operand combinations. Done means the example compiles while existing array operation behavior remains supported.

Written by the indexing model from the issue text.

Description

It would be useful for me to be able to use references to scalars instead of owned instances when performing operations on arrays.

e.g., this fails:

let arr1 = array!([1, 2, 3]);
let four: i32 = 4;
let arr2 = arr1 + &four; //error

I naively tried modifying the ops macros to accept references but kept getting a conflicting implementation error. It seems that the compiler is worried that someone will come along an add an implementation to StaticOperand for reference types:

    = note: downstream crates may implement trait `impl_ops::ScalarOperand` for type `&_`

...which is strange because there's a 'static type bound on ScalarOperand?

In any case, if anyone has any guidance on how to proceed, I'd greatly appreciate it! I'm happy to open a PR with a nudge in the right direction.

Dominant language
Rust
Stars
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Forks
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PR merge metrics
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