Conditional variable assignment

JavaScript performance comparison

Test case created by Mathias Bynens and last updated

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Test Ops/sec
x = x || y; when x is falsy
 
var foo; // foo === undefined
foo = foo || 'default';
// foo === 'default';
 pending…
x || (x = y); when x is falsy
 
var foo; // foo === undefined
foo || (foo = 'default');
// foo === 'default';
 pending…
!x && (x = y); when x is falsy
 
var foo; // foo === undefined
!foo && (foo = 'default');
// foo === 'default';
 pending…
x = x || y; when x is truthy
 
var foo = 'value';
foo = foo || 'default';
// foo === 'value';
 pending…
x || (x = y); when x is truthy
 
var foo = 'value';
foo || (foo = 'default');
// foo === 'value';
 pending…
!x && (x = y); when x is truthy
 
var foo = 'value';
!foo && (foo = 'default');
// foo === 'value';
 pending…

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1 comment

Mathias Bynens (revision owner) commented : ∞

FWIW, I just cleared the results.

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