Katharos: Monads, functors, and immutable data for Python
Katharos is a library that introduces functional programming concepts to Python, including monads, functors, and immutable data structures. It allows for type-safe code and provides tools for handling optional values and modeling errors as values. The library is available for installation via pip and includes comprehensive documentation for users.
- ▪Katharos provides functional programming abstractions for Python, such as Monads and Functors.
- ▪Users can handle optional values without None checks using the Maybe type.
- ▪The library allows for chaining operations with do-notation and combining values with the Semigroup operator.
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Katharos Functional programming abstractions for Python — Monads, Applicatives, Functors, and immutable data structures for composable, type-safe code. Installation pip install katharos Quick Start Handle optional values without None checks: from katharos.types import Maybe result = Maybe[int].Just(5) | (lambda x: Maybe[int].Just(x * 2)) # Just(10) nothing = Maybe[int].Nothing() | (lambda x: Maybe[int].Just(x * 2)) # Nothing() Model errors as values instead of exceptions: from katharos.types import Result def parse_int(s: str) -> Result[ValueError, int]: try: return Result.Success(int(s)) except ValueError as e: return Result.Failure(e) parse_int("42") | (lambda n: Result[ValueError, int].Success(n * 2)) # Success(84) parse_int("??") | (lambda n: Result[ValueError, int].Success(n * 2)) #…
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