Test if a value is a parseable JSON string.
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> Test if a value is a parseable JSON string.
``bash`
npm install @stdlib/assert-is-json
`javascript`
var isJSON = require( '@stdlib/assert-is-json' );
#### isJSON( value )
Tests if a value is a parseable JSON string.
`javascript
var value = '{"a":5}';
var bool = isJSON( value );
// returns true
`
- The implementation validates that the input value is a string literal. For all other inputs, the method returns false.
- The implementation validates that a string begins with either [ or { and ends with a corresponding ] or }, respectively. Hence, the method will return false for the following strings, despite JSON.parse accepting their input:
- ' (e.g., '5')'
- (e.g., 'true')'null'
-
- The implementation wraps JSON.parse inside a try/catch. Hence, this function cannot be optimized by the compiler during runtime. Nevertheless, using this function is better than embedding a try/catch within a larger function which could be optimized in the absence of a try/catch.
`javascript
var isJSON = require( '@stdlib/assert-is-json' );
var bool = isJSON( '{"a":5}' );
// returns true
bool = isJSON( '{a":5}' );
// returns false
`
*
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