1 | import { Observable } from '../Observable';
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2 | import { AsyncSubject } from '../AsyncSubject';
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3 | import { Subscriber } from '../Subscriber';
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4 | import { SchedulerAction, SchedulerLike } from '../types';
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5 | import { map } from '../operators/map';
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6 | import { canReportError } from '../util/canReportError';
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7 | import { isScheduler } from '../util/isScheduler';
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8 | import { isArray } from '../util/isArray';
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9 |
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10 | /* tslint:disable:max-line-length */
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11 | /** @deprecated resultSelector is deprecated, pipe to map instead */
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12 | export function bindNodeCallback(callbackFunc: Function, resultSelector: Function, scheduler?: SchedulerLike): (...args: any[]) => Observable<any>;
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13 |
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14 | export function bindNodeCallback<R1, R2, R3, R4>(callbackFunc: (callback: (err: any, res1: R1, res2: R2, res3: R3, res4: R4, ...args: any[]) => any) => any, scheduler?: SchedulerLike): (...args: any[]) => Observable<any[]>;
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15 | export function bindNodeCallback<R1, R2, R3>(callbackFunc: (callback: (err: any, res1: R1, res2: R2, res3: R3) => any) => any, scheduler?: SchedulerLike): () => Observable<[R1, R2, R3]>;
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16 | export function bindNodeCallback<R1, R2>(callbackFunc: (callback: (err: any, res1: R1, res2: R2) => any) => any, scheduler?: SchedulerLike): () => Observable<[R1, R2]>;
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17 | export function bindNodeCallback<R1>(callbackFunc: (callback: (err: any, res1: R1) => any) => any, scheduler?: SchedulerLike): () => Observable<R1>;
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18 | export function bindNodeCallback(callbackFunc: (callback: (err: any) => any) => any, scheduler?: SchedulerLike): () => Observable<void>;
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19 |
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20 | export function bindNodeCallback<A1, R1, R2, R3, R4>(callbackFunc: (arg1: A1, callback: (err: any, res1: R1, res2: R2, res3: R3, res4: R4, ...args: any[]) => any) => any, scheduler?: SchedulerLike): (...args: any[]) => Observable<any[]>;
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21 | export function bindNodeCallback<A1, R1, R2, R3>(callbackFunc: (arg1: A1, callback: (err: any, res1: R1, res2: R2, res3: R3) => any) => any, scheduler?: SchedulerLike): (arg1: A1) => Observable<[R1, R2, R3]>;
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22 | export function bindNodeCallback<A1, R1, R2>(callbackFunc: (arg1: A1, callback: (err: any, res1: R1, res2: R2) => any) => any, scheduler?: SchedulerLike): (arg1: A1) => Observable<[R1, R2]>;
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23 | export function bindNodeCallback<A1, R1>(callbackFunc: (arg1: A1, callback: (err: any, res1: R1) => any) => any, scheduler?: SchedulerLike): (arg1: A1) => Observable<R1>;
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24 | export function bindNodeCallback<A1>(callbackFunc: (arg1: A1, callback: (err: any) => any) => any, scheduler?: SchedulerLike): (arg1: A1) => Observable<void>;
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25 |
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26 | export function bindNodeCallback<A1, A2, R1, R2, R3, R4>(callbackFunc: (arg1: A1, arg2: A2, callback: (err: any, res1: R1, res2: R2, res3: R3, res4: R4, ...args: any[]) => any) => any, scheduler?: SchedulerLike): (...args: any[]) => Observable<any[]>;
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27 | export function bindNodeCallback<A1, A2, R1, R2, R3>(callbackFunc: (arg1: A1, arg2: A2, callback: (err: any, res1: R1, res2: R2, res3: R3) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2) => Observable<[R1, R2, R3]>;
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28 | export function bindNodeCallback<A1, A2, R1, R2>(callbackFunc: (arg1: A1, arg2: A2, callback: (err: any, res1: R1, res2: R2) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2) => Observable<[R1, R2]>;
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29 | export function bindNodeCallback<A1, A2, R1>(callbackFunc: (arg1: A1, arg2: A2, callback: (err: any, res1: R1) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2) => Observable<R1>;
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30 | export function bindNodeCallback<A1, A2>(callbackFunc: (arg1: A1, arg2: A2, callback: (err: any) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2) => Observable<void>;
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31 |
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32 | export function bindNodeCallback<A1, A2, A3, R1, R2, R3, R4>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, callback: (err: any, res1: R1, res2: R2, res3: R3, res4: R4, ...args: any[]) => any) => any, scheduler?: SchedulerLike): (...args: any[]) => Observable<any[]>;
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33 | export function bindNodeCallback<A1, A2, A3, R1, R2, R3>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, callback: (err: any, res1: R1, res2: R2, res3: R3) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3) => Observable<[R1, R2, R3]>;
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34 | export function bindNodeCallback<A1, A2, A3, R1, R2>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, callback: (err: any, res1: R1, res2: R2) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3) => Observable<[R1, R2]>;
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35 | export function bindNodeCallback<A1, A2, A3, R1>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, callback: (err: any, res1: R1) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3) => Observable<R1>;
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36 | export function bindNodeCallback<A1, A2, A3>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, callback: (err: any) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3) => Observable<void>;
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37 |
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38 | export function bindNodeCallback<A1, A2, A3, A4, R1, R2, R3, R4>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, callback: (err: any, res1: R1, res2: R2, res3: R3, res4: R4, ...args: any[]) => any) => any, scheduler?: SchedulerLike): (...args: any[]) => Observable<any[]>;
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39 | export function bindNodeCallback<A1, A2, A3, A4, R1, R2, R3>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, callback: (err: any, res1: R1, res2: R2, res3: R3) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3, arg4: A4) => Observable<[R1, R2, R3]>;
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40 | export function bindNodeCallback<A1, A2, A3, A4, R1, R2>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, callback: (err: any, res1: R1, res2: R2) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3, arg4: A4) => Observable<[R1, R2]>;
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41 | export function bindNodeCallback<A1, A2, A3, A4, R1>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, callback: (err: any, res1: R1) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3, arg4: A4) => Observable<R1>;
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42 | export function bindNodeCallback<A1, A2, A3, A4>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, callback: (err: any) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3, arg4: A4) => Observable<void>;
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43 |
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44 | export function bindNodeCallback<A1, A2, A3, A4, A5, R1, R2, R3, R4>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5, callback: (err: any, res1: R1, res2: R2, res3: R3, res4: R4, ...args: any[]) => any) => any, scheduler?: SchedulerLike): (...args: any[]) => Observable<any[]>;
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45 | export function bindNodeCallback<A1, A2, A3, A4, A5, R1, R2, R3>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5, callback: (err: any, res1: R1, res2: R2, res3: R3) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5) => Observable<[R1, R2, R3]>;
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46 | export function bindNodeCallback<A1, A2, A3, A4, A5, R1, R2>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5, callback: (err: any, res1: R1, res2: R2) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5) => Observable<[R1, R2]>;
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47 | export function bindNodeCallback<A1, A2, A3, A4, A5, R1>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5, callback: (err: any, res1: R1) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5) => Observable<R1>;
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48 | export function bindNodeCallback<A1, A2, A3, A4, A5>(callbackFunc: (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5, callback: (err: any) => any) => any, scheduler?: SchedulerLike): (arg1: A1, arg2: A2, arg3: A3, arg4: A4, arg5: A5) => Observable<void>; /* tslint:enable:max-line-length */
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49 |
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50 | export function bindNodeCallback(callbackFunc: Function, scheduler?: SchedulerLike): (...args: any[]) => Observable<any[]>;
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51 | /**
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52 | * Converts a Node.js-style callback API to a function that returns an
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53 | * Observable.
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54 | *
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55 | * <span class="informal">It's just like {@link bindCallback}, but the
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56 | * callback is expected to be of type `callback(error, result)`.</span>
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57 | *
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58 | * `bindNodeCallback` is not an operator because its input and output are not
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59 | * Observables. The input is a function `func` with some parameters, but the
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60 | * last parameter must be a callback function that `func` calls when it is
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61 | * done. The callback function is expected to follow Node.js conventions,
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62 | * where the first argument to the callback is an error object, signaling
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63 | * whether call was successful. If that object is passed to callback, it means
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64 | * something went wrong.
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65 | *
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66 | * The output of `bindNodeCallback` is a function that takes the same
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67 | * parameters as `func`, except the last one (the callback). When the output
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68 | * function is called with arguments, it will return an Observable.
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69 | * If `func` calls its callback with error parameter present, Observable will
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70 | * error with that value as well. If error parameter is not passed, Observable will emit
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71 | * second parameter. If there are more parameters (third and so on),
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72 | * Observable will emit an array with all arguments, except first error argument.
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73 | *
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74 | * Note that `func` will not be called at the same time output function is,
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75 | * but rather whenever resulting Observable is subscribed. By default call to
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76 | * `func` will happen synchronously after subscription, but that can be changed
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77 | * with proper `scheduler` provided as optional third parameter. {@link SchedulerLike}
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78 | * can also control when values from callback will be emitted by Observable.
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79 | * To find out more, check out documentation for {@link bindCallback}, where
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80 | * {@link SchedulerLike} works exactly the same.
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81 | *
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82 | * As in {@link bindCallback}, context (`this` property) of input function will be set to context
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83 | * of returned function, when it is called.
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84 | *
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85 | * After Observable emits value, it will complete immediately. This means
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86 | * even if `func` calls callback again, values from second and consecutive
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87 | * calls will never appear on the stream. If you need to handle functions
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88 | * that call callbacks multiple times, check out {@link fromEvent} or
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89 | * {@link fromEventPattern} instead.
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90 | *
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91 | * Note that `bindNodeCallback` can be used in non-Node.js environments as well.
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92 | * "Node.js-style" callbacks are just a convention, so if you write for
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93 | * browsers or any other environment and API you use implements that callback style,
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94 | * `bindNodeCallback` can be safely used on that API functions as well.
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95 | *
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96 | * Remember that Error object passed to callback does not have to be an instance
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97 | * of JavaScript built-in `Error` object. In fact, it does not even have to an object.
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98 | * Error parameter of callback function is interpreted as "present", when value
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99 | * of that parameter is truthy. It could be, for example, non-zero number, non-empty
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100 | * string or boolean `true`. In all of these cases resulting Observable would error
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101 | * with that value. This means usually regular style callbacks will fail very often when
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102 | * `bindNodeCallback` is used. If your Observable errors much more often then you
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103 | * would expect, check if callback really is called in Node.js-style and, if not,
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104 | * switch to {@link bindCallback} instead.
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105 | *
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106 | * Note that even if error parameter is technically present in callback, but its value
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107 | * is falsy, it still won't appear in array emitted by Observable.
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108 | *
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109 | * ## Examples
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110 | * ### Read a file from the filesystem and get the data as an Observable
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111 | * ```ts
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112 | * import * as fs from 'fs';
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113 | * const readFileAsObservable = bindNodeCallback(fs.readFile);
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114 | * const result = readFileAsObservable('./roadNames.txt', 'utf8');
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115 | * result.subscribe(x => console.log(x), e => console.error(e));
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116 | * ```
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117 | *
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118 | * ### Use on function calling callback with multiple arguments
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119 | * ```ts
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120 | * someFunction((err, a, b) => {
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121 | * console.log(err); // null
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122 | * console.log(a); // 5
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123 | * console.log(b); // "some string"
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124 | * });
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125 | * const boundSomeFunction = bindNodeCallback(someFunction);
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126 | * boundSomeFunction()
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127 | * .subscribe(value => {
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128 | * console.log(value); // [5, "some string"]
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129 | * });
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130 | * ```
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131 | *
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132 | * ### Use on function calling callback in regular style
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133 | * ```ts
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134 | * someFunction(a => {
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135 | * console.log(a); // 5
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136 | * });
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137 | * const boundSomeFunction = bindNodeCallback(someFunction);
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138 | * boundSomeFunction()
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139 | * .subscribe(
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140 | * value => {} // never gets called
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141 | * err => console.log(err) // 5
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142 | * );
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143 | * ```
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144 | *
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145 | * @see {@link bindCallback}
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146 | * @see {@link from}
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147 | *
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148 | * @param {function} func Function with a Node.js-style callback as the last parameter.
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149 | * @param {SchedulerLike} [scheduler] The scheduler on which to schedule the
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150 | * callbacks.
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151 | * @return {function(...params: *): Observable} A function which returns the
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152 | * Observable that delivers the same values the Node.js callback would
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153 | * deliver.
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154 | * @name bindNodeCallback
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155 | */
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156 | export function bindNodeCallback<T>(
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157 | callbackFunc: Function,
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158 | resultSelector: Function|SchedulerLike,
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159 | scheduler?: SchedulerLike
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160 | ): (...args: any[]) => Observable<T> {
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161 |
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162 | if (resultSelector) {
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163 | if (isScheduler(resultSelector)) {
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164 | scheduler = resultSelector;
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165 | } else {
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166 | // DEPRECATED PATH
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167 | return (...args: any[]) => bindNodeCallback(callbackFunc, scheduler)(...args).pipe(
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168 | map(args => isArray(args) ? resultSelector(...args) : resultSelector(args))
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169 | );
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170 | }
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171 | }
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172 |
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173 | return function(this: any, ...args: any[]): Observable<T> {
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174 | const params: ParamsState<T> = {
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175 | subject: undefined,
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176 | args,
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177 | callbackFunc,
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178 | scheduler,
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179 | context: this,
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180 | };
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181 | return new Observable<T>(subscriber => {
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182 | const { context } = params;
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183 | let { subject } = params;
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184 | if (!scheduler) {
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185 | if (!subject) {
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186 | subject = params.subject = new AsyncSubject<T>();
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187 | const handler = (...innerArgs: any[]) => {
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188 | const err = innerArgs.shift();
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189 |
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190 | if (err) {
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191 | subject.error(err);
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192 | return;
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193 | }
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194 |
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195 | subject.next(innerArgs.length <= 1 ? innerArgs[0] : innerArgs);
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196 | subject.complete();
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197 | };
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198 |
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199 | try {
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200 | callbackFunc.apply(context, [...args, handler]);
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201 | } catch (err) {
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202 | if (canReportError(subject)) {
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203 | subject.error(err);
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204 | } else {
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205 | console.warn(err);
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206 | }
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207 | }
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208 | }
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209 | return subject.subscribe(subscriber);
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210 | } else {
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211 | return scheduler.schedule<DispatchState<T>>(dispatch, 0, { params, subscriber, context });
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212 | }
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213 | });
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214 | };
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215 | }
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216 |
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217 | interface DispatchState<T> {
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218 | subscriber: Subscriber<T>;
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219 | context: any;
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220 | params: ParamsState<T>;
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221 | }
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222 |
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223 | interface ParamsState<T> {
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224 | callbackFunc: Function;
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225 | args: any[];
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226 | scheduler: SchedulerLike;
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227 | subject: AsyncSubject<T>;
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228 | context: any;
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229 | }
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230 |
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231 | function dispatch<T>(this: SchedulerAction<DispatchState<T>>, state: DispatchState<T>) {
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232 | const { params, subscriber, context } = state;
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233 | const { callbackFunc, args, scheduler } = params;
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234 | let subject = params.subject;
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235 |
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236 | if (!subject) {
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237 | subject = params.subject = new AsyncSubject<T>();
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238 |
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239 | const handler = (...innerArgs: any[]) => {
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240 | const err = innerArgs.shift();
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241 | if (err) {
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242 | this.add(scheduler.schedule<DispatchErrorArg<T>>(dispatchError, 0, { err, subject }));
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243 | } else {
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244 | const value = innerArgs.length <= 1 ? innerArgs[0] : innerArgs;
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245 | this.add(scheduler.schedule<DispatchNextArg<T>>(dispatchNext, 0, { value, subject }));
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246 | }
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247 | };
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248 |
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249 | try {
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250 | callbackFunc.apply(context, [...args, handler]);
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251 | } catch (err) {
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252 | this.add(scheduler.schedule<DispatchErrorArg<T>>(dispatchError, 0, { err, subject }));
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253 | }
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254 | }
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255 |
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256 | this.add(subject.subscribe(subscriber));
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257 | }
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258 |
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259 | interface DispatchNextArg<T> {
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260 | subject: AsyncSubject<T>;
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261 | value: T;
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262 | }
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263 |
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264 | function dispatchNext<T>(arg: DispatchNextArg<T>) {
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265 | const { value, subject } = arg;
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266 | subject.next(value);
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267 | subject.complete();
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268 | }
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269 |
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270 | interface DispatchErrorArg<T> {
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271 | subject: AsyncSubject<T>;
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272 | err: any;
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273 | }
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274 |
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275 | function dispatchError<T>(arg: DispatchErrorArg<T>) {
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276 | const { err, subject } = arg;
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277 | subject.error(err);
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278 | }
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