Files
purescript-node-stream-pipes/src/Node.Stream.Object.js

54 lines
1.6 KiB
JavaScript

import Stream from "stream";
/** @type {(s: Stream.Readable | Stream.Transform) => () => boolean} */
export const isReadableImpl = (s) => () => s.readable;
/** @type {(s: Stream.Writable | Stream.Readable) => () => boolean} */
export const isClosedImpl = (s) => () => s.closed;
/** @type {(s: Stream.Writable | Stream.Transform) => () => boolean} */
export const isWritableImpl = (s) => () => s.writable;
/** @type {(s: Stream.Readable | Stream.Transform) => () => boolean} */
export const isReadableEndedImpl = (s) => () => s.readableEnded;
/** @type {(s: Stream.Writable | Stream.Transform) => () => boolean} */
export const isWritableEndedImpl = (s) => () => s.writableEnded;
/** @type {(s: Stream.Writable | Stream.Transform) => () => void} */
export const endImpl = (s) => () => s.end();
/** @type {<WriteResult>(o: {ok: WriteResult, wouldBlock: WriteResult, closed: WriteResult}) => (s: Stream.Writable | Stream.Transform) => (a: unknown) => () => WriteResult} */
export const writeImpl =
({ ok, wouldBlock, closed }) =>
(s) =>
(a) =>
() => {
if (s.closed || s.writableEnded) {
return closed;
}
if (s.write(a)) {
return ok;
} else {
return wouldBlock;
}
};
/** @type {<ReadResult>(o: {just: (_a: unknown) => ReadResult, wouldBlock: ReadResult, closed: ReadResult}) => (s: Stream.Readable | Stream.Transform) => () => ReadResult} */
export const readImpl =
({ just, closed, wouldBlock }) =>
(s) =>
() => {
if (s.closed || s.readableEnded) {
return closed;
}
const a = s.read();
if (a === null) {
return wouldBlock;
} else {
return just(a);
}
};