If a predicate function returns a truthy value, return
x; otherwise, returny.
var ifelseAsync = require( '@stdlib/utils/if-else-async' );If a predicate function returns a truthy value, returns x; otherwise, returns y.
var randu = require( '@stdlib/random/base/randu' );
function predicate( clbk ) {
setTimeout( onTimeout, 0 );
function onTimeout() {
clbk( null, randu() > 0.5 );
}
}
function done( error, result ) {
if ( error ) {
throw error;
}
console.log( result );
}
ifelseAsync( predicate, 1.0, -1.0, done );The predicate function is provided a single argument:
clbk: callback to invoke uponpredicatefunction completion
The callback accepts two arguments:
error: error objectbool: condition used to determine whether to returnxory
The done callback is invoked upon function completion and is provided at most two arguments:
error: error objectresult: eitherxory
- 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 ifelseAsync = require( '@stdlib/utils/if-else-async' );
var i;
function next() {
ifelseAsync( predicate, 'BOOP', 'beep', done );
}
function predicate( clbk ) {
setTimeout( onTimeout, 0 );
function onTimeout() {
clbk( null, randu() > 0.9 );
}
}
function done( error, result ) {
if ( error ) {
throw error;
}
i += 1;
console.log( result );
if ( i < 100 ) {
next();
}
}
i = 0;
next();