S0033: unsupported + operands

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

Explanation

The + operator is overloaded only for Int, Float, String, and arrays in Rellum. Both operands must first have compatible types, and the resulting operation must be one of numeric addition, string concatenation, or array concatenation.

Common causes

• adding Bool, Char, record, enum, tuple, or function values
• using + between values of different types
• expecting implicit conversion before concatenating strings

Canonical fixes

• convert values explicitly before string concatenation

Before:

message = "count: " + count

After:

message = "count: " + to_string(count)

• use a field or projection with an addable type

Before:

sum = left + right

After:

sum = left.value + right.value

• use arrays on both sides for array concatenation

Before:

items = items + item

After:

items = items + [item]

Code example

message = "count: " + count

Links

• RellC diagnostic overview