:IF... :ELSE... :ENDIF

Use the :IF and :ENDIF script statements to create a conditional block in your script. The script analyzes an expression and runs statements written in the block when a particular condition is met. If the condition is not met, the script either continues with the next line after the conditional block, or runs :ELSE statements if applicable.

Syntax

:IF Condition
[Statements]
[:ELSE]
[Other Statements]
:ENDIF

Parameters

• :IF
  Starts a conditional block

• Condition
  Mathematical expression that determines whether to run the statements in the conditional block
  Format: script literals, script variables, script functions or numbers, with the possible results true or false

• Statements
  On or more script statements to execute when the Condition is true
  Format: script statement

• :ELSE
  Starts a branch that executes when the condition is false

• Other Statements
  One or more script statements to execute when the Condition is false
  Format: script statement

Notes:

• You must define the script variables that you use in a condition before the conditional block.
• Use OR as the keyword to link a condition to several values, or to link several conditions. Write OR conditions in the following structure:
  ValueComparison operatorComparison Value[OR Comparison Value...]
  Example: :IF &DEP# = "EDP" OR "AE"
• You can use up to 13 ORs in a Condition.
• You do not have to include :ELSE statements.
• You can nest :IF blocks to an unlimited depth.
• Trailing blank spaces are not considered in string comparisons. Therefore, blank strings always are equal independent on their length.
• Leading zeros are only ignored in numerical comparisons.

Important! The :IF statement does not recognize differences in characters beyond the first 1024 characters in a string.

A condition contains one of the following comparison operators:

Operator	Short form	Rule
=	EQ	This expression is "True" if at least one of the comparison values equals the Value.
<>	NE	This expression is "True" when none of the comparison values equals the Value.
<	LT	This expression is "True" if one comparison value corresponds to the defined condition.
>	GT
<=	LE
>=	GE

Examples

The following comparison of &a with &b returns true because the trailing blanks are eliminated before comparing the strings.

:set &a= 'a   '
:set &b= 'a'
:if &a = &b
:print 'true'
:endif

A numerical comparison takes place when both comparison values of a condition have a numerical value (data types signed, unsigned or float). In all other cases, a string comparison takes place.

The following condition is true:

:IF "0" = "0"

An alphanumeric comparison takes place when there are no numerical values.

The following condition is false:

:IF "0" = "abc"

Script lengths are not checked during the comparison process. The following condition is true because S comes before U in the alphabet:

:IF "Smith" < "UX"

In conditions that include several OR keywords, the behavior depends on the operator.

In the following example, one of the values must apply in order to meet the condition.

:IF &WD# = "MON" OR "TUE" OR "WED"

The following condition is only met if the variable does not comply with any of the three values.

:IF &WD# <> "THU" OR "FRI" OR "SAT"

See also: