# EXPRESSIONS

For the following commands, CALC, IF, ELSEIF, SETVAR, and WHILE, the

Command Interpreter (CI) assumes that the argument supplied on the

command line is an expression. Additionally, you can force the CI to

evaluate an expression for any command by enclosing the expression in

square brackets and preceding the brackets with an exclamation point, e.g. ![].

Variables, functions and operators are combined to form CI expressions.

An expression can be as simple as a constant, e.g. 1, TRUE, or "abc",

or complex, such as

finfo (filename,"eof") mod (2^8)

The CI also does partial expression evaluation. For instance, in the

following example, the CI will not evaluate (B) if (A) is FALSE:

(A) AND (B)

Or, in this example, if (A) is TRUE, the CI does not evaluate (B):

(A) OR (B)

In other words, the CI reads an expression from left to right, and

performs the minimum evaluation necessary.

For additional information, enter VARIABLES, FUNCTIONS, and

OPERATORS at the HELP prompt.