Extract a function with explicit boundary contract

Most 'refactor this' prompts produce noisy diffs. This one extracts one function with a written contract you can sanity-check before applying.

Prompt

Refactor the code below by extracting {{EXTRACT_TARGET}} into its own function.

Before writing any code, produce:
1. The proposed function signature (name, parameters, return type).
2. A one-paragraph contract describing inputs, outputs, side effects, and edge cases.
3. The exact lines that move into the new function.
4. The exact lines that change at the call site.

Then produce the refactored code as a single diff. Do not change anything outside the extraction.

Code:
```
{{CODE}}
```

Variables to fill in

{{EXTRACT_TARGET}}
{{CODE}}

How to use this prompt

Copy the prompt above (Copy button on the top-right).
Replace each {{VAR}} with your own value. Variables: {{EXTRACT_TARGET}}{{CODE}}.
Paste it into one of the recommended tools below.
Iterate: tighten constraints in the prompt if the output is generic.

Why this prompt is structured this way

The prompt is split into explicit steps because LLMs do better when the path is named, not implied. Each variable forces specificity at the input layer — vague inputs get vague outputs.

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