@basic-streams/take/index.js

take operator for basic-streams

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
function take(n, stream) {
    return function (cb) {
        var state = { cb: cb, count: 0 };
        function stop() {
            if (state !== null) {
                var disposer_1 = state.disposer;
                state = null;
                if (disposer_1) {
                    disposer_1();
                }
            }
        }
        function onEvent(x) {
            if (state !== null) {
                var cb_1 = state.cb;
                cb_1(x);
                state.count++;
                if (state.count >= n) {
                    stop();
                }
            }
        }
        if (n === 0) {
            state = null;
        }
        var disposer = stream(onEvent);
        if (state === null) {
            disposer();
        }
        else {
            state.disposer = disposer;
        }
        return stop;
    };
}
exports.default = take;