-- rdinl > R (L t) t — read stdin as a list of lines (newlines stripped).
-- Pairs naturally with map/flt for line-oriented text processing pipelines.
-- Returns Err on I/O failure or WASM targets.
--
-- This example reads stdin lines, filters non-empty ones, and counts them.
-- It can only run in a pipeline; the engine harness skips it (no -- run: marker).
main>n
lines=rdinl!
len (flt (\l;>(len l) 0) lines)