IF statement

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Single-line conditional statement
Condition
Composite condition

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IF statement

In french: Si

The conditional IF statement allows you to run an action according to a condition.

Example

IF Customer.CalculatedAge > 60 THEN
	Elderly += 1
ELSE IF Customer.CalculatedAge > 18 THEN
	Adult += 1
ELSE IF Customer.CalculatedAge > 4 THEN
	Child += 1
ELSE 
	Baby += 1
END

// Use of 'IN'
IF Customer.City IN ("PARIS", "MARSEILLE", "LYON") THEN
	Info("You live in one of the 3 biggest cities in France")
END

// Use of 'NOT x IN'
IF NOT Customer.City IN ("PARIS", "MARSEILLE", "LYON") THEN
	Info("You don't live in one of the 3 biggest cities in France")
END

// Use of 'NOT IN' (from version 23)
IF Customer.City NOT IN ("PARIS", "MARSEILLE", "LYON") THEN
	Info("You don't live in one of the 3 biggest cities in France")
END

Syntax

Syntax 1

IF <Condition> THEN
<Action if condition is True>
[ELSE
<Action if condition is False>]
END

Syntax 2

IF <Condition> THEN
<Action if condition is True>
[ELSE <Action if condition is False>]

Syntax 3 Hide the details

IF <Condition> THEN <Action if condition is True> [ELSE <Action if condition is False>]

<IF>:

Marks the beginning of the statement block.

<Condition>:

Condition to check.

<THEN>:

Actions to perform if the condition is True.

<Action if condition is True>:

Action to perform if the condition is True.

<ELSE>:

Actions to perform if the condition is False (optional).

<Action if condition false>:

Action to perform if the condition is False (optional).

<END>:

Marks the end of the statement block.

Syntax 4 Hide the details

IF <Condition 1> THEN
<Action if condition 1 is True>
[ELSE IF <Condition 2> THEN
<Action if condition 2 is True>
[ELSE IF <Condition 3> THEN
<Action if condition 3 is True>
[...]]]
END

<IF>:

Marks the beginning of the statement block.

<Condition 1>:

1st condition to check.

<THEN>:

Actions to perform if the previous condition is True.

<Action if condition 1 is True>:

Action to perform if the 1st condition is True.

<ELSE IF>:

Checks the next condition if the previous condition is False (optional).

<Condition 2>:

2nd condition to check (optional).

<Action if condition 2 is True>:

Action to perform if the 2nd condition is True and if the 1st condition is False (optional).

<Condition 3>:

3rd condition to check.

<Action if condition 3 is True>:

Action to perform if the 3rd condition is True and if the 1st and 2nd conditions are False.

<END>:

Marks the end of the statement block.

Remarks

Single-line conditional statement

You also have the ability to use the following syntax:

Detailed syntax:


<Result>	Variable to assign with the condition result.
<Condition>	Condition to check.
<Expression 1>	Value assigned to <Result> if the condition is True.
<Expression 2>	Value assigned to <Result> if the condition is False.

Equivalence:

IF <Condition> THEN
<Result> = <Expression 1>
ELSE
<Result> = <Expression 2>
END

Note: The single-line conditional expression can be used directly in an expression.

Example: If age is greater than sixty, count one more person. Otherwise, don't change the number of people.

Elderly = Customer.CalculatedAge > 60? Elderly +1 ELSE Elderly

Condition

<Condition> can take the following format:


<Value> = <Expression>	Equality test
<Value> < <Expression>	Comparison test
<Value> <= <Expression>	Comparison test
<Value> > <Expression>	Comparison test
<Value> >= <Expression>	Comparison test
<Value> = <Minimum Expression> TO <Maximum Expression>	<Value> must be included between the minimum expression and the maximum expression
<Minimum Expression> <= <Value> <= <Maximum Expression>
<Value> IN (<Expression1>, <Expression2>, ..., <Expression N>)	<Value> is compared to the result of a list of expressions. All the expressions found in the list are evaluated. The operator returns True if <Value> is equal to at least one of the expressions, False if <Value> is equal to none of the expressions.
<Value> NOT IN (<Expression1>, <Expression2>, ..., <Expression N>)	<Value> is compared to the result of a list of expressions. All the expressions found in the list are evaluated. The operator returns False if <Value> is equal to at least one of the expressions, True if <Value> is equal to none of the expressions.
<Value> _IN_ (<Expression1>, <Expression2>, ..., <Expression N>)	<Value> is compared to the result of a list of expressions. The expressions are evaluated from left to right. As soon as an expression is equal to <Value>, the remaining expressions are not evaluated and the operator returns True. If <Value> is equal to no expression, the operator returns False.
<Value> NOT _IN_ (<Expression1>, <Expression2>, ..., <Expression N>)	<Value> is compared to the result of a list of expressions. The expressions are evaluated from left to right. As soon as an expression is equal to <Value>, the remaining expressions are not evaluated and the operator returns False. If <Value> is equal to no expression, the operator returns True. Caution: There must be a space between "NOT" and "_IN_".

Composite condition

The AND and OR keywords are used to perform logical operations and to create composite conditions.

For example:

IF Customer.City = "Montpellier" AND Customer.Title = "Mr" THEN
	ManMontpellier ++   // Number of men living in Montpellier
END
 
IF Customer.City = "Montpellier" OR Customer.City = "Lyon" THEN
	MontpellierLyon ++ // Number of customers living in Montpellier or in Lyon
END

The conditions made of AND and OR are entirely evaluated.

For example:
A > 10 AND B < 20

Even if the first condition (A > 10) is false, the second condition (B < 20) will be checked.

Optimizing the evaluation of composite conditions: Use the _AND_ and _OR_ keywords. If the first condition is false (A>10 in our example), the second condition (B<20 in our example) will not be checked. For more details, see Logical operators.