TestStand declares a number of constant values. Some values, like the keywords True and False, are similar to values used in other environments. Other values are used less often. The following table lists all known constant definitions and their common uses.

Note TestStand is not case sensitive for constant names. For example, true is the same as True and TRUE.
Table 7. Special Constant Values
Constant Definition Use
1.23e-4 Floating Point Constant Range approximately 1.7E-308 to 1.7E+308 with 15 significant digits.
Note The Use Localized Decimal Point option on the Localization tab of the Station Options dialog box and your operating system settings determine the decimal point character you use in a floating point number.
1234, 0xFFFF, 0b1011 32-bit Integer Constant Range -2147483648 to 4294967295. TestStand supports hexadecimal and binary formats with this type of constant with the use of the 0x and 0b prefixes. TestStand treats hexadecimal and binary versions of these constants as unsigned values with a range of 0 to 4294967295. TestStand converts and represents these constants internally as double-precision, floating-point numbers.
1234i64, 0xFFFFi64, 0b1011i64 64-bit Signed Integer Constant Range -9223372036854775808i64 to 9223372036854775807i64. TestStand supports hexadecimal and binary formats with this type of constant with the use of the 0x and 0b prefixes. However, if the high order bit is set, TestStand interprets the constant as a negative value.
1234ui64, 0xFFFFui64, 0b1011ui64 64-bit Unsigned Integer Constant Range 0ui64 to 18446744073709551615ui64. TestStand supports hexadecimal and binary formats with this type of constant with the use of the 0x and 0b prefixes.
True/False Boolean Constant True or False.
"1234wxyz" String Constant Refer to Special String Characters for more information.
@"C:\Windows\temp" Unescaped String Constant Add an @ before the enclosed quotes to turn a string constant into an unescaped string constant. Unlike for regular string constants, backslashes are left as is instead of specifying an escape sequence. Use "" for " within an unescaped string constant.
Nothing Object Reference Constant You can determine whether an object reference refers to an object by comparing the reference to Nothing. You can release the object to which an object reference refers by setting the value of the reference to Nothing in an expression. TestStand handles the garbage collection of references set equal to Nothing when it retrieves all memory that has gone out of scope. This reference is the equivalent of Nothing in Microsoft Visual Basic .NET, null in C# .NET, or NULL in LabWindows/CVI and Microsoft Visual C++.
PI PI Constant (3.141592...) The ratio of the circumference of a circle to its diameter.
NAN Not a Number A numeric value that is not a valid number. The value is equivalent to a quiet NaN value. TestStand also displays NAN for signaling NaN values. IND is a special kind of quiet NaN value.
Note TestStand treats NAN and IND as equivalent in expression comparisons.
IND Indeterminate Number A numeric value that is indeterminate. The value is equivalent to a special kind of quiet NaN value. Some numeric operations, such as Sqrt(-1), will result in an indeterminate value.
Note TestStand treats NAN and IND as equivalent in expression comparisons.
INF Infinite Number A numeric value that is infinite or negative infinite. Equivalent to an INF value in Visual C++.
Note The Use Localized Decimal Point option on the Localization tab of the Station Options dialog box and your operating system settings determine the decimal point character you use in a floating point number.