Use restrictions

Although most DML instructions and operators can be used in any expression, certain restrictions exist. The following table summarizes where you can use DML elements and where you cannot.

Instruction, statement
or operator
Expression types

Check
Constraints

Variable
initialization

Decision
Paths

Mapping
Rules

literals Available Available Available Available

variable reading

Available

 

Available

Available

variable assignment

Available

 

Available

Available

explicit value assignment using $

Available

Available  

Available

+, -, *, / and ** on numbers

Available

Available

Available

Available

+ and * on strings

Available

Available

Available

Available

node paths

Available

 

Available

Available

=, <>, <, <=, > and >= operators

Available

Available

Available

Available

and, or, xor and not

Available

Available

Available

Available

if…then…else statement

Available

Available

Available

Available

switch statement

Available

Available

Available

Available

defined and undefined operators

Available

 

Available

Available

loop and while statements

Available

Available

Available

Available

break and next instructions

Available

Available

Available

Available

loop on statement

Available

 

Available

Available

times and times…do statements

 

 

 

Available

for each and for each…do

 

 

 

Available

select statement

 

 

 

Available

tree statement

 

 

 

Available

exit statement

Available

Available

Available

Available

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