Variables used in JSON files

• Author: Kasper Torbjorn
• Updated: 3/18/2020

JSON standard is a subset of JavaScript language and thus supports similar variable types

1. Binary values – boolean type

Boolean expression has one of two values: true or false (which are sometimes represented as integers 1 and 0, respectively). Although it is a simple enough data type, many unexpected errors may arise due to fact that JSON interprets as true the following non-boolean values:

• any non-zero number type, for example, values 1, -50, or 3.41

• any non-empty text type, for example “text” , “00”, or even string of value “false”.

• binary value true

Boolean values false is also given to such values as:

• number 0

• number -0 (has no meaning and is resolved to 0)

• empty text value (“”)

• any declared variable without any value

• value null

• binary value false

• non-numerical value NaN (for values that cannot be represented as numbers)

2. Number type – number, integer

   Both types are similar to each other. Integer type is given to integer number values. Number type is given to floating-point numbers and is a dynamic type. Converting number type to integer type implies loss of precision.

3. Character string type – string

   String is a sequence of zero or more unicode characters, which follows that an empty string value (“” ) is as string of length 0.

4. Array type – array

   Array is a list of zero or more values of single type, for example, an array containing the names of days of the week.

5. Object type – object

   Objects can hold any types of data.

6. Value null

   Value null is not a separate data type, but indicates absence of any value. It is an accepted convention to use null to represent no object value.