time-to-botec

README.md (3698B)

---

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 @license Apache-2.0
 
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 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
 
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 See the License for the specific language governing permissions and
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 # Try Function
 
 > Wrap a function in a try/catch block.
 
 <section class="usage">
 
 ## Usage
 
 ```javascript
 var wrap = require( '@stdlib/utils/try-function' );
 ```
 
 #### wrap( fcn )
 
 Wraps a `function` in a `try/catch` block.
 
 ```javascript
 function fcn() {
     throw new Error( 'beep boop' );
 }
 
 var f = wrap( fcn );
 
 var out = f();
 if ( out instanceof Error ) {
     console.error( out.message );
     // => 'beep boop'
 }
 ```
 
 The returned `function` has the same signature as the wrapped `function`.
 
 ```javascript
 function fcn( a, b, c, d ) {
     var sum = a + b + c + d;
     if ( sum < 10 ) {
         throw new Error( 'invalid arguments. Arguments must sum to a number greater than or equal to 10.' );
     }
     return sum;
 }
 
 var f = wrap( fcn );
 
 var out = f( 5, 6, 7, 8 );
 // returns 26
 
 out = f( 1, 2, 3, 1 );
 // returns <Error>
 ```
 
 If provided an asynchronous `function`, the returned `function` only traps `errors` which occur during the current event loop tick.
 
 <!-- run throws: true -->
 
 ```javascript
 function fcn( a, b, clbk ) {
     if ( !a ) {
         throw new Error( 'invalid argument.' );
     }
     setTimeout( onTimeout, 0 );
     function onTimeout() {
         if ( !b ) {
             throw new Error( 'invalid argument.' );
         }
         clbk();
     }
 }
 
 function done() {
     console.log( 'beep' );
 }
 
 var f = wrap( fcn );
 
 var out = f( null, 5, done );
 // returns <Error>
 
 out = f( true, null, done );
 // returns undefined
 ```
 
 </section>
 
 <!-- /.usage -->
 
 <section class="notes">
 
 ## Notes
 
 -   Isolating `try/catch` blocks as separate wrapped `functions` prevents a parent scope from permanently entering optimization hell.
 -   If a function throws a literal, the literal is serialized as a `string` and returned as an `Error` object.
 
 </section>
 
 <!-- /.notes -->
 
 <section class="examples">
 
 ## Examples
 
 <!-- run throws: true -->
 
 <!-- eslint no-undef: "error" -->
 
 ```javascript
 var wrap = require( '@stdlib/utils/try-function' );
 
 function beep( str ) {
     if ( typeof str !== 'string' ) {
         throw new TypeError( 'invalid argument. Must provide a string primitive. Value: `' + str + '`.' );
     }
     return 'beep ' + str;
 }
 
 function boop( str, clbk ) {
     if ( typeof str !== 'string' ) {
         throw new TypeError( 'invalid argument. Must provide a string primitive. Value: `' + str + '`.' );
     }
     setTimeout( done, 1000 );
 
     function done() {
         if ( str !== 'beep' ) {
             throw new Error( 'invalid argument. String must equal `beep`. Value: `' + str + '`.' );
         }
         clbk( str + ' boop' );
     }
 }
 
 function done( str ) {
     if ( str !== 'beep boop' ) {
         throw new Error( 'huh?' );
     }
 }
 
 var out;
 var f;
 
 // Synchronous...
 f = wrap( beep );
 
 out = f( 'boop' );
 console.log( out );
 // => 'beep boop'
 
 out = f( null );
 console.log( out.message );
 // => '...'
 
 // Asynchronous...
 f = wrap( boop );
 
 out = f( 'beep', done );
 console.log( out );
 // => undefined
 
 out = f( 'foo', done );
 console.log( out );
 // => undefined
 ```
 
 </section>
 
 <!-- /.examples -->
 
 <section class="links">
 
 </section>
 
 <!-- /.links -->