Grammar conventions for Rule formulae

These conventions apply to the grammar used to define the formula for Rules.

Phrases

• Each Rule consists of 1 - n phrases.
• Each phrase can be enclosed in brackets () when there is more than one phrase in a line, implying that there must be an equal amount of “(“ and “)” brackets in the Rule.
• Phrases must be separated by an “AND” or an “OR” when there is more than one phrase in a line.
• A phrase can be preceded with “NOT” (phrase).

Expressions

• Each phrase consists of 1 - n Expressions.
• Each expression can be enclosed in brackets (), when there is more than one expression in a line.
• Expressions must be separated by an “AND” or an “OR” when there is more than one expression in a line.
• An Expression can consist of one of the following:
• • Option Operand Value, for example (THERMOSTAT = ‘120’)
  • NOT SPECIFIED Option, for example (NOT (SPECIFIED THERMOSTAT))
  • SPECIFIED Option, for example (SPECIFIED THERMOSTAT)
  • Value IN Option, for example (‘PETROL’ IN FUEL)
• An Option is followed by an Operand, defined in the table below, except where it is preceded by “NOT SPECIFIED”, “SPECIFIED” or “Value IN”.
• An open bracket “(“ is always followed by “NOT” or an Option, except when it is preceded by “IN”.
• If the Operand contains “IN” then multiple values may be defined as follows.
• • Separated by commas.
  • Allowed values must conform to the Data Type specified for the Rule. For example “FUEL IN (‘abc’, ‘def’)”
  • The last value is followed by a “)”.

Values

• String values are enclosed in single quote marks.
• Numeric values are not enclosed in quote marks; they are classified as Integer or Float values and are recognized by the decimal point “.”.
  The values may be preceded by a “+” or “-“.
• Date values are enclosed in single quote marks and consist of 8 numeric characters ‘ccyymmdd’.
• There is no distinction between upper case and lower case characters in Options and operands.

Valid Operands

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