Difference between "0" and null

Danielle · **Posted:** Sat Mar 11, 2006 8:03 pm

Simply enough, the ability for eScript to tell the difference between the number "0" and a variable that is "null" or "nothing".

Austin · **Posted:** Sat Mar 11, 2006 10:01 pm

Uhm these things already exist

( !value ) - works for all of the above

( value != 0 ) // Integer 0
( value != error ) // Error
( value != "" ) // empty string

Marilla · **Posted:** Sun Mar 12, 2006 1:09 pm

The typical way I test where I need to differentiate between a 0 value and an error or null is this:

Code:

If (!value && value != 0)
 'only runs on error
elseif (value == 0)
  'only runs if value is explicitly 0
else
  'etc
endif

You could also:

Code:

If (value == error)
 'catches ALL errors, no matter the type
  print(cstr(error));
elseif (!value)
  'since error is trapped above, this would run on 0
else
  'etc
endif

Firedancer · **Posted:** Wed Mar 15, 2006 2:04 am

forgot one option....

Code:

if(value+1)
 //...then it's not error :P
endif

works too hehe. But I'd commonly not use it, it's not really nice-to-read code *g*

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Difference between "0" and null

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