(arg) - Rust

argument positions in call sites and function parameters

(arg pos? val?)

Where:

1. pos: position in the list (1-based) *
2. val: value at that position *

Examples

Find calls that pass None as a fallback value.

(call _ (arg 2 (id None)))

Selects in lines { 1 } but not in { 2 }:

cache.get(key, None);
cache.get(key, Some(value));

---

Find handlers whose first parameter is ctx.

(fun _ (arg 1 (id ctx)))

Selects in lines { 1 } but not in { 2 }:

fn handle(ctx: &Context, req: Request) {}
fn render(req: Request) {}

---

Arguments

pos

1. Number
2. Numeric Range

Does NOT support: Composition — Free-form Selection — Refinement — Replacement

val

1. Identifier: shorthand for (id)
   
2. String: shorthand for (str)
   
3. (:into)
4. (:nearest)
5. (:and)
6. (:or)
7. (:not)
8. (:text)
9. (:kind)
10. (:replace)
11. (:replace-in)
12. (:capture)
13. (:ref)
14. (call)
15. (enum)
16. (fun)
17. (id)
18. (match-arm)
19. (mem)
20. (num)
21. (str)