The Microsoft Excel File Format - OpenOffice.org

3 Formulas
3.2 Token Classes
3.2.1 Classified Tokens
All function operators and most operand tokens exist in 3 different versions: as reference class token, value class token,
and array class token. The token class depends on which type of data the involved operator expects. Sometimes only 1
or 2 token classes are valid for a token (for example, array class tokens cannot exist as reference class tokens, but they
can exist as value class tokens).
• Reference class token: The reference address itself, independent of the cell contents.
• Value class token: A value (a constant, a function result, or one specific value from a dereferenced cell range).
• Array class token: An array of values (array of constant values, an array function result, or all values of a cell range).
The structure of the 8-bit identifier of a classified token is described in the following table.
Bit Mask Contents
4-0 1F H Basic token identifier
6-5 60 H 01 2 = Reference class token (token range 20 H -3F H )
10 2 = Value class token (token range 40 H -5F H )
11 2 = Array class token (token range 60 H -7F H )
7 80 H 0 2 (zero)
The token class is marked in the names of the tokens. The names of reference class tokens contain a trailing “R”, value
class tokens contain a trailing “V”, and the names of array class tokens a trailing “A”.
Example: The tArea token (➜3.9.3) is no specific token, but refers to the three tokens tAreaR (25 H ),
tAreaV (45 H ), and tAreaA (65 H ).
• The tAreaR token represents the cell range address itself.
• The tAreaV token represents one value in the cell range (for example the value in the current row or column).
• The tAreaA token represents the entire array of values in the cell range.
3.2.2 Operand Classes
Each operator and operand has a default token class, called operand class. For operands itself, the operand class is
dependent on the data the token represents. The operand class of operators is determined from its return value. For
functions (tokens tFunc, ➜3.7.1, and tFuncVar, ➜3.7.2), the operand class is dependent on the value the function
returns. Classified tokens can represent their operand class, other tokens cannot.
Examples for operand classes:
Term Operand class Token identifier Description
A1 Reference tRefR Reference to cell A1
A1 A1 Reference tIsect Return value of the intersection operator
INDEX(A1,1,1) Reference tFuncVarR Return value of the INDEX function
2 Value tInt The constant 2
2+3 Value tAdd Return value of the addition operator
SUM(2,3) Value tFuncVarV Return value of the SUM function
{2,3} Array tArrayA The constant array {2,3}
TREND({2,3}) Array tFuncVarA Return value of the TREND function
32