Translate Code From One Language to Another

This prompt converts a working piece of code from one programming language to another while insisting on idiomatic target-language style rather than a clumsy line-for-line port. It's the tool to reach for when migrating a script, prototyping in a new stack, or porting a library helper you don't want to rewrite from scratch. The instruction to flag library substitutions and annotate judgment calls is the important part — it surfaces exactly the places where a translation can silently change behavior.

What you can expect back

package config

import (
    "encoding/json"
    "os"
    "strings"
)

// LoadConfig reads a JSON file and returns its keys lowercased.
// Note: Python dicts preserve insertion order; Go maps do not, so
// don't rely on key ordering downstream.
func LoadConfig(path string) (map[string]any, error) {
    raw, err := os.ReadFile(path)
    if err != nil {
        return nil, err // Go returns errors explicitly instead of raising
    }
    var data map[string]any
    if err := json.Unmarshal(raw, &data); err != nil {
        return nil, err
    }
    out := make(map[string]any, len(data))
    for k, v := range data {
        out[strings.ToLower(k)] = v
    }
    return out, nil
}

Key differences:
- Python's implicit exceptions become explicit (error) return values.
- json.load -> json.Unmarshal, which needs the bytes read first via os.ReadFile.
- The dict comprehension becomes a plain range loop; Go has no comprehensions.

Illustrative example — your results will vary by tool and inputs.

Get sharper results

• 01Include the imports and any helper functions the snippet calls, otherwise the model has to guess at the library behavior it's replacing.
• 02Name exact versions when behavior differs across them (Python 2 vs 3, Java 8 vs 21) so the model picks the right idioms and standard-library APIs.
• 03Ask it to also translate the tests, or to write target-language tests, so you can confirm behavior actually matches rather than trusting the port by eye.
• 04When the source relies on a third-party package, tell the model which target ecosystem library you prefer, or it may pick one you don't want to add as a dependency.
• 05Watch the 'meaningful decision' comments closely — things like integer division, default mutability, or null handling are where translated code most often diverges.

Adapt it for your case