> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sifr.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# SIFR-FLOW-0005: Control-flow condition has an unsupported type.

> Control-flow condition has an unsupported type.

`SIFR-FLOW-0005` belongs to the **Control flow** diagnostic family. It means: control-flow condition has an unsupported type.

## Why It Happens

The control-flow graph cannot satisfy Sifr's static rules. Repair unsupported statements, invalid loop control, non-boolean conditions, missing returns, or unreachable code.

<Info>
  Use `sifr --explain SIFR-FLOW-0005` locally to see the renderer's exact message template and any machine-applicable suggestions for the compiler version you are running.
</Info>

## Erroneous Code

```python theme={null}
def label(value: int) -> str:
    if value > 0:
        return "positive"
```

## How To Fix It

Repair the control-flow shape: put break/continue inside loops, return on every required path, and use supported loop and assignment forms.

## Fixed Code

```python theme={null}
def label(value: int) -> str:
    if value > 0:
        return "positive"
    return "zero or negative"
```

## Details

| Field                  | Value                                                             |
| ---------------------- | ----------------------------------------------------------------- |
| Code                   | `SIFR-FLOW-0005`                                                  |
| Family                 | `FLOW`                                                            |
| Severity               | Error                                                             |
| Stability              | stable                                                            |
| Owner                  | `sifr_lowering::lower::control_flow_conditions`                   |
| Representative fixture | `crates/sifr/tests/e2e/fail/if_condition_numeric_truthiness.sifr` |

See the [Error Codes index](/diagnostics/error-codes) for the complete catalog.