When we have to resort to different actions depending on the value of a variable: we can use Evaluate-endevaluate. It is just like Switch case in C language.

Eg:

move '12' to Month.

evaluate Month

when '12' display 'you are right'

when '01' display 'it is not new year dear!'

when other display 'try again Boy!'

end-evaluate.

So it will display three different strings depending on what is moved into the variable Month.

In short evaluate is a replacement of nested-if.

If 1+1>2 then display '1+1>2 is wrong'

else if 1+1<2 then display '1+1<2 is wrong too'

else display 'you are right'

end-if

end-if

could be replaced by:

evaluate true

when 1+1>2 display '1+1>2 is wrong'

when 1+1<2 display '1+1<2 is wrong too'

when other display 'you are right'

end-evaluate.

The Evaluate statement can be used in replacement of Nested-IF statements. These are also potentially used by combining the logical operators.

FOR EG:

evaluate a > 100 and a < 500

move 'good' to b

evaluate a > 500 or a < 1000

move 'better' to b

evaluate a > 1000 or a < 5000

move 'best' to b

end-evaluate.