Direct Assignment of Macro Variables (DEFINE-!ENDDEFINE command)

The macro command !LET assigns values to macro variables. The syntax is as follows:

!LET !var = expression

• The expression must be either a single token or enclosed in parentheses.
• The macro variable !var cannot be a macro keyword, and it cannot be the name of one of the arguments within the macro definition. Thus, !LET cannot be used to change the value of an argument.
• The macro variable !var can be a new variable or one previously assigned by a !DO command or another !LET command.

Example

!LET !a = 1
!LET !b = !CONCAT(ABC,!SUBSTR(!1,3,1),DEF)
!LET !c = (!2 ~= !NULL)

• The first !LET sets !a equal to 1.
• The second !LET sets !b equal to ABC followed by 1 character taken from the third position of !1 followed by DEF.
• The last !LET sets !c equal to 0 (false) if !2 is a null string or to 1 (true) if !2 is not a null string.