S0002: parameter needs explicit type annotation

Generated from rellum-diagnostics/src/db.rs.

Explanation

Function parameters are part of a function's public type. Rellum does not infer those parameter types from the function body, so each parameter needs an annotation before the analyzer can type-check calls, imports, or generic instantiations.

Common causes

• writing a function parameter without : Type
• expecting the compiler to infer a parameter type from arithmetic or calls in the body
• omitting annotations on a generic function's parameters

Canonical fixes

• add an explicit parameter type

Before:

double(x) : Int = x * 2

After:

double(x: Int) : Int = x * 2

• annotate every parameter in a generic function

Before:

identity[T](x) : T = x

After:

identity[T](x: T) : T = x

Code example

double(x) : Int = x * 2

Links

• RellC diagnostic overview