set <variable> to <definition>

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set <variable> to <definition>

Summary

Defines a variable as an object, a collection, or a value.

Syntax

set `<variable>' to <definition> [in <list> / from <object>] [where <test>*] ;

Description

Use this construct in the definitions part of a rule to declare a local variable. Variables allow you to write more concise rules by using a short, convenient identifier to represent a value or the result of an expression. A local variable can be used anywhere within this same rule, but is not available in other rules.

You should enclose the name of each variable in single quotes. This is compulsory for variable names that contain spaces. While it is not essential to enclose one word variable names in single quotes, it is strongly recommended that you do so, to make them easier to identify and to reduce the risk of confusion.

Example

The following examples show how to define a variable as an object.

definitions
   set 'i' to an item;
   set 'house' to a house 
      where the price of this house is more than 1000;

The following examples show how to define a variable as a literal, string, or collection.

definitions
   set 'category' to Gold ;
   set 's' to "a string";
   set 'expensive items' to all items 
      in the items of the shopping cart of the customer 
      where the price of each item is more than 200;

The following example shows how to define a variable as the result of an expression.

definitions
   set 'expr' to the price of the car of the customer + 100;
   set 'h2' to the house of the customer 
      where the price of this house is more than 1000;

The following example shows how to define a variable as another variable.

definitions
   set 'expr2' to 'expr';