Brandon Lucas
0b5abece5f
Standard examples (examples/standard/): - hello_world: Basic effect usage - fizzbuzz: Classic programming exercise - factorial: Recursive and tail-recursive versions - primes: Prime number generation - guessing_game: Interactive Random + Console effects - stdlib_demo: Demonstrates List, String, Option, Math modules Showcase examples (examples/showcase/): - ask_pattern: Resumable effects for config/environment - custom_logging: Custom effect with handler - early_return: Fail effect for clean error handling - effect_composition: Combining multiple effects - higher_order: Closures and function composition - pattern_matching: ADTs and exhaustive matching Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
40 lines
926 B
Plaintext
40 lines
926 B
Plaintext
// Effect Composition - Combine multiple effects cleanly
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//
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// Unlike monad transformers (which have ordering issues),
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// effects can be freely combined without boilerplate.
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// Each handler handles its own effect, ignoring others.
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//
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// Expected output:
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// [LOG] Starting computation
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// Generated: 7
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// [LOG] Processing value
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// [LOG] Done
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// Result: 14
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effect Log {
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fn log(msg: String): Unit
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}
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fn computation(): Int with {Log, Random} = {
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Log.log("Starting computation")
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let x = Random.int(1, 10)
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Log.log("Processing value")
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let result = x * 2
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Log.log("Done")
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result
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}
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handler consoleLog: Log {
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fn log(msg) = Console.print("[LOG] " + msg)
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}
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fn main(): Unit with {Console} = {
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let result = run computation() with {
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Log = consoleLog
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}
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Console.print("Generated: " + toString(result / 2))
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Console.print("Result: " + toString(result))
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}
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let output = run main() with {}
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