IExpression

The IExpression interface contains properties that are used to work with an expression, by which some values are calculated.

Comments

An expression is set as a string using the IExpression.AsString property. To check if the expression is correct, use the IExpression.Valid property.

Arithmetic operations , numbers, comparison symbols and round brackets.
Built-in functions.
Connected custom methods. For details about this see the Connecting Custom Methods to Expression Editor section.
Application functions. An application function must be written in the Fore language and saved in the unit. To use application functions in the expression, determine full path to the function in the following format: <Module identifier>.<Function name>[(Parameters values)].
Time and dummy variables. They are applied on composing an expression in the Modeling and Forecasting tool. To paste time or dummy variable in the expression, enter its name and parameters using keyboard. For details about this see the Time and Dummy Variables section.
Statistical methods of application and system classes. To use methods in the expression, specify full path to the method in the format: <Module name>.<Class name>.<Method name>. For details about this see the sections: Classes, System Assembly Classes, IStatistics and MathFin.
Parameters, data and metadata of the source.

Properties

Property name

Brief description

The AsString property determines the expression, by which values will be calculated, as a string of symbols.

The Empty property returns True if the expression is not set.

The ErrorInfo property returns information on errors that may occur when parsing the expression.

The References property determines the list of units/forms containing the custom functions that are used to create an expression.

The StringHandler property determines an object that is used to track changes of expression terms.

The Substitutions property returns the collection of substitutions used in expressions.

The ThrowException property determines whether an exception is thrown when a parsed expression contains errors.

The Valid property returns whether an expression is valid.

Description