flix-docs

Use the |> pipe operator to avoid temporary variables, place the receiver as the last function argument, and propagate Algebraic Effects to callers instead of running them locally. Run handlers only at entry points like main or @Test where DefaultHandler applies.

Reserved words like spawn and run fail even as record field names, producing indirect errors such as "Expected ',' before '='". Rename them to alternatives like start or walkR, and consult the full reserved-word list in the project rules.

Prefer the Flix standard library: use Fs for file operations, BufReader for buffered reading, Math.Random for randomness, and type-module conversion functions like Int32.fromString. Only fall back to Java interop when no standard equivalent exists, with imports at module top level.

Declare effects in the function signature and let them propagate rather than calling run locally, which would turn everything into IO. Prefer DefaultHandler, then built-in handlers via with, and hand-written handlers only as a last resort, chaining multiple handlers in one run block.

No, List.sortBy and List.sort are not stable in Flix 0.75.1; equal-key elements may not keep input order. When order matters, use List.zipWithIndex to add a tiebreaker key so the composite sort key is unique.

@Test functions must return Unit and use the Assert module for assertions. Write one assert per test using tuples or lists for multiple values, avoid pattern-match branching in tests, and add clear comments including ASCII art for complex scenarios.