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JSON.parse fallback for undefined array to avoid exception

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-1

I'm parsing my array and everything is OK if it is defined:

JSON.parse(myArray);

However I get an exception in case if myArray is undefined.

What is the best fallback for it, is there anything better than this:

JSON.parse(myArray || '[]');

similar like we first verify the object to avoid an exception if undefined

if (obj) 
//do something with obj.something

So, is there anything shorter than

JSON.parse(myArray || '[]'); 

Thank you.

javascript arrays undefined fallback

share|improve this question

asked Mar 25 at 13:15

HaradzieniecHaradzieniec

4,0662020 gold badges8686 silver badges174174 bronze badges

• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  That seems pretty short as it is.
  
  – Pointy
  Mar 25 at 13:17
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  That's pretty much as good as you'll get short of modifying the lib function to check undefined
  
  – SoZettaSho
  Mar 25 at 13:18
  

  
  
  
  

add a comment | 

-1

I'm parsing my array and everything is OK if it is defined:

JSON.parse(myArray);

However I get an exception in case if myArray is undefined.

What is the best fallback for it, is there anything better than this:

JSON.parse(myArray || '[]');

similar like we first verify the object to avoid an exception if undefined

if (obj) 
//do something with obj.something

So, is there anything shorter than

JSON.parse(myArray || '[]'); 

Thank you.

javascript arrays undefined fallback

share|improve this question

asked Mar 25 at 13:15

HaradzieniecHaradzieniec

4,0662020 gold badges8686 silver badges174174 bronze badges

• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  That seems pretty short as it is.
  
  – Pointy
  Mar 25 at 13:17
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  That's pretty much as good as you'll get short of modifying the lib function to check undefined
  
  – SoZettaSho
  Mar 25 at 13:18
  

  
  
  
  

add a comment | 

I'm parsing my array and everything is OK if it is defined:

JSON.parse(myArray);

However I get an exception in case if myArray is undefined.

What is the best fallback for it, is there anything better than this:

JSON.parse(myArray || '[]');

similar like we first verify the object to avoid an exception if undefined

if (obj) 
//do something with obj.something

So, is there anything shorter than

JSON.parse(myArray || '[]'); 

Thank you.

javascript arrays undefined fallback

share|improve this question

asked Mar 25 at 13:15

HaradzieniecHaradzieniec

4,0662020 gold badges8686 silver badges174174 bronze badges

JSON.parse(myArray);

JSON.parse(myArray || '[]');

if (obj) 
//do something with obj.something

JSON.parse(myArray || '[]'); 

share|improve this question

asked Mar 25 at 13:15

HaradzieniecHaradzieniec

4,0662020 gold badges8686 silver badges174174 bronze badges

share|improve this question

asked Mar 25 at 13:15

HaradzieniecHaradzieniec

4,0662020 gold badges8686 silver badges174174 bronze badges

asked Mar 25 at 13:15

HaradzieniecHaradzieniec

4,0662020 gold badges8686 silver badges174174 bronze badges

asked Mar 25 at 13:15

HaradzieniecHaradzieniec

4,0662020 gold badges8686 silver badges174174 bronze badges

1 Answer
1

active

oldest

votes

2

Your current method works just fine as well. I don't really see a reason to change it but if you feel you need to two options come to mind:

First, you could initialize myArray with it defaulted to an empty array before it gets its values assigned.

var myArray = '[]';

Otherwise if myArray is a parameter passed to a method you are parsing it from, you can default it in the arguments section.

function dosomething(myArray = '[]') 
 JSON.parse(myArray);

share|improve this answer

edited Mar 28 at 12:18

answered Mar 25 at 13:21

Daniel DeesDaniel Dees

13722 silver badges1111 bronze badges

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  right, but it should be myArray = "[]", not just []
  
  – georg
  Mar 25 at 14:25
  

  
  
  
  

add a comment | 

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2

Your current method works just fine as well. I don't really see a reason to change it but if you feel you need to two options come to mind:

First, you could initialize myArray with it defaulted to an empty array before it gets its values assigned.

var myArray = '[]';

Otherwise if myArray is a parameter passed to a method you are parsing it from, you can default it in the arguments section.

function dosomething(myArray = '[]') 
 JSON.parse(myArray);

share|improve this answer

edited Mar 28 at 12:18

answered Mar 25 at 13:21

Daniel DeesDaniel Dees

13722 silver badges1111 bronze badges

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  right, but it should be myArray = "[]", not just []
  
  – georg
  Mar 25 at 14:25
  

  
  
  
  

add a comment | 

2

Your current method works just fine as well. I don't really see a reason to change it but if you feel you need to two options come to mind:

First, you could initialize myArray with it defaulted to an empty array before it gets its values assigned.

var myArray = '[]';

Otherwise if myArray is a parameter passed to a method you are parsing it from, you can default it in the arguments section.

function dosomething(myArray = '[]') 
 JSON.parse(myArray);

share|improve this answer

edited Mar 28 at 12:18

answered Mar 25 at 13:21

Daniel DeesDaniel Dees

13722 silver badges1111 bronze badges

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  right, but it should be myArray = "[]", not just []
  
  – georg
  Mar 25 at 14:25
  

  
  
  
  

add a comment | 

Your current method works just fine as well. I don't really see a reason to change it but if you feel you need to two options come to mind:

First, you could initialize myArray with it defaulted to an empty array before it gets its values assigned.

var myArray = '[]';

Otherwise if myArray is a parameter passed to a method you are parsing it from, you can default it in the arguments section.

function dosomething(myArray = '[]') 
 JSON.parse(myArray);

share|improve this answer

edited Mar 28 at 12:18

answered Mar 25 at 13:21

Daniel DeesDaniel Dees

13722 silver badges1111 bronze badges

var myArray = '[]';

function dosomething(myArray = '[]') 
 JSON.parse(myArray);

share|improve this answer

edited Mar 28 at 12:18

answered Mar 25 at 13:21

Daniel DeesDaniel Dees

13722 silver badges1111 bronze badges

answered Mar 25 at 13:21

Daniel DeesDaniel Dees

13722 silver badges1111 bronze badges

answered Mar 25 at 13:21

Daniel DeesDaniel Dees

13722 silver badges1111 bronze badges