UniBasic Commands Reference - Rocket Software

1-369 UniBasic Commands Reference
A single-line statement that includes the INPUT command as a part of the
THEN clause might not produce the results you expect. For example, the
following statements produce no output:
IF X = 1 THEN INPUT TEST ELSE PRINT "X NE 1"
To correct this problem, enter each clause of the statement on a separate line,
or use the IN() function to obtain input from theterminal or input queue.
With null value handling turned on, a test on expr that is the null value returns false.
For an overview of how the null value affects UniBasic, see Developing UniBasic
Applications.
Tip: You can nest IF/THEN/ELSE statements, but a CASE statement might be more
efficient.
Examples
In the following example, the program statement tests if the variable SUPPLY is less
than the variable DEMAND. If the comparison is true, program control is transferred
to the statement labeled REORDER.
IF SUPPLY < DEMAND THEN GOSUB REORDER
In the next example, the program segment compares INCOME to TARGET. UniData
executes the first branch if the comparison is true, or executes the second group of
statements if the comparison is false.
IF INCOME < TARGET THEN
PRINT "Income less than target figure."
END ELSE
PRINT "Income equal to or greater than target!"
END
Related Commands
UniBasic
CASE, LOOP/REPEAT, NULL