Functional Programming Rating

After editing or creating a code file, output a minimalist rating of its adherence to functional programming principles.

When to Rate

Rate files containing programming logic after:

• Creating new code files
• Editing existing code files

Do NOT rate:

• Configuration files (JSON, YAML, etc.)
• Markup files (HTML, CSS, Markdown, .md files)
• Data files
• Documentation files

Rating Criteria

Evaluate the file against these 7 principles (score out of 10):

1. PURITY – Pure functions (same inputs → same outputs, no side effects)
2. IMMUTABILITY – No mutations (use spread operators, return new values)
3. EXPLICIT DEPENDENCIES – Dependencies as parameters, not globals
4. EFFECTS AT EDGES – I/O and side effects at boundaries, not mixed with logic
5. ERRORS AS VALUES – Result/Either types instead of exceptions for expected failures
6. DECLARATIVE STYLE – map/filter/reduce over imperative loops
7. COMPOSITION – Small, focused, composable functions

Scoring Guidelines

• 9-10: Exemplary FP – follows nearly all principles
• 7-8: Strong FP – follows most principles with minor violations
• 5-6: Mixed approach – some FP patterns, some imperative
• 3-4: Mostly imperative – minimal FP adherence
• 1-2: Non-functional – direct violations of most principles

Output Format

After completing file edits, append this exact table format at the bottom of your response:

Allegiance to Functional Programming
┌─────────────────────────┬───────┐
│ File                    │ Score │
├─────────────────────────┼───────┤
│ filename.ext            │ X/10  │
└─────────────────────────┴───────┘

Replace filename.ext with the actual file name and X with the numeric score. Include ONLY this table – no explanations, no breakdown, no additional commentary.

Example

After editing userService.ts, append:

Allegiance to Functional Programming
┌─────────────────────────┬───────┐
│ File                    │ Score │
├─────────────────────────┼───────┤
│ userService.ts          │ 7/10  │
└─────────────────────────┴───────┘