If a function does not return an error, invoke a callback with the function result; otherwise, invoke a callback with a value
y.
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var trycatchAsync = require( '@stdlib/utils-async-try-catch' );If a function x does not return an error, invokes a done callback with the function result; otherwise, invokes a done callback with a value y.
var randu = require( '@stdlib/random-base-randu' );
function x( clbk ) {
setTimeout( onTimeout, 0 );
function onTimeout() {
if ( randu() > 0.5 ) {
return clbk( null, 1.0 );
}
clbk( new Error( 'oops' ) );
}
}
function done( error, result ) {
if ( error ) {
console.log( error.message );
}
console.log( result );
}
trycatchAsync( x, -1.0, done );The function x is provided a single argument:
clbk: callback to invoke upon function completion
The callback accepts two arguments:
error: error objectresult: function result
The done callback is invoked upon function completion and is provided two arguments:
error: error objectresult: either the result ofxor the provided valuey
If the function x does not return a truthy error argument, the error argument provided to the done callback is null. If x does return a truthy error argument, the done callback is invoked with both the error and the provided value y.
- Execution is not guaranteed to be asynchronous. To guarantee asynchrony, wrap the
donecallback in a function which either executes at the end of the current stack (e.g.,nextTick) or during a subsequent turn of the event loop (e.g.,setImmediate,setTimeout).
var randu = require( '@stdlib/random-base-randu' );
var trycatchAsync = require( '@stdlib/utils-async-try-catch' );
var i;
function next() {
trycatchAsync( x, 'beep', done );
}
function x( clbk ) {
setTimeout( onTimeout, 0 );
function onTimeout() {
if ( randu() > 0.9 ) {
return clbk( null, 'BOOP' );
}
clbk( new Error( 'oops' ) );
}
}
function done( error, result ) {
if ( error ) {
console.log( error.message );
}
i += 1;
console.log( result );
if ( i < 100 ) {
return next();
}
}
i = 0;
next();@stdlib/utils/try-catch: if a function does not throw, return the function return value; otherwise, returny.@stdlib/utils/async/try-then: if a function does not return an error, invoke a callback with the function result; otherwise, invoke a second function.
This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.
See LICENSE.
Copyright © 2016-2023. The Stdlib Authors.
