In the GLaDOS language, there are several different data types. These include:

  • int - An integer value
<int> ::= 'Int64 MinValue' .. 'Int64 MaxValue'
  • float - A floating point value
<float> ::= 'Float64 MinValue' .. 'Float64 MaxValue'
  • char - A single character
<char> ::= 'An ascii character'
  • string - A string of characters
<string> ::= 'An array of ascii characters between double quotes'
  • array - An array of values regardless of type
<array> ::= { <value> ',' <value> }
  • bool - A boolean value
<bool> ::= 'True' | 'False'
  • NULL - A null value
<null> ::= 'Null'


To declare a variable, use the following syntax:

<identifier> = <value>;

Variables are not typed, and can be assigned any value.

The value of a variable can be changed at any time.