RAIN.Belief.ConditionalExpression Class Reference

ConditionalExpression represents a logical expression similar to a C++ or C# conditional. Conditionals can be represented as a left-hand-side (lhs), right-hand-side (rhs) and an infix operator (op) as in (lhs op rhs). Operators supported are GT, LT, GE, LE, EQ, NEQ, APPROX, NAPPROX, NO_OP Nested expressions and expressions with variables are supported. (i.e., lhs and rhs can be any valid Expression) More...

List of all members.

Public Types
enum	ComparisonType {   GT, LT, GE, LE,   EQ, NEQ, APPROX, NAPPROX,   NO_OP }
	Comparison type enum. More...
Public Member Functions
	ConditionalExpression ()
	Default constructor.
	ConditionalExpression (Expression expr1, ComparisonType comparisonOperator, Expression expr2)
	Constructor including lhs, op, and rhs.
void	SetInvalid ()
	Invalidate the ConditionalExpression.
void	RenameVariable (string originalName, string newName)
	Rename a variable in all nested expressions.
void	SetExpression (Expression expr1, ComparisonType comparisonOperator, Expression expr2)
	Reset the ConditionalExpression with a new rhs, operator, and lhs.
bool	Evaluate (float deltaTime, ActionContext actionContext)
	Evaluate will calculate the true or false value of the conditional expression by evaluating the lhs and rhs, then comparing them using the operator. The current VariableContext will be used to bind values for any nested variables. If either lhs or rhs are missing, Evaluate returns false. If either lhs or rhs evaluate to NaN (not a number) Evaluate will return false.
override string	ToString ()
	ToString() will return a string representation of the ConditionalExpression which may differ from the original text parsed to create this expression.
Properties
bool	IsValid [get]
	Is the conditional expression valid and can it be evaluated successfully? Checks to ensure that the Conditional Expression is formed of valid lhs and rhs expressions, and that the comparison operator is not a no-op.
string	ExpressionAsEntered [get, set]
	ExpressionAsEntered returns the text used to initially describe the ConditionalExpression, if the expression was created from parsing a script or manual entry. This is useful when supporting user editing of invalid expressions.

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Detailed Description

ConditionalExpression represents a logical expression similar to a C++ or C# conditional. Conditionals can be represented as a left-hand-side (lhs), right-hand-side (rhs) and an infix operator (op) as in (lhs op rhs). Operators supported are GT, LT, GE, LE, EQ, NEQ, APPROX, NAPPROX, NO_OP Nested expressions and expressions with variables are supported. (i.e., lhs and rhs can be any valid Expression)

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Member Enumeration Documentation

enum RAIN::Belief::ConditionalExpression::ComparisonType

Comparison type enum.

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Constructor & Destructor Documentation

RAIN.Belief.ConditionalExpression.ConditionalExpression

(

)

Default constructor.

RAIN.Belief.ConditionalExpression.ConditionalExpression	(	Expression	expr1,
		ComparisonType	comparisonOperator,
		Expression	expr2
	)

Constructor including lhs, op, and rhs.

Parameters:

expr1	The left-hand-side expression
comparisonOperator	The comparison operator
expr2	The right-hand-side expression

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Member Function Documentation

bool RAIN.Belief.ConditionalExpression.Evaluate	(	float	deltaTime,
		ActionContext	actionContext
	)

Evaluate will calculate the true or false value of the conditional expression by evaluating the lhs and rhs, then comparing them using the operator. The current VariableContext will be used to bind values for any nested variables. If either lhs or rhs are missing, Evaluate returns false. If either lhs or rhs evaluate to NaN (not a number) Evaluate will return false.

Parameters:

deltaTime

timestep to use when evaluating. this wlil replace the variable "t" in all expressions

Returns:

true if the expression evaluates to true, false otherwise

void RAIN.Belief.ConditionalExpression.RenameVariable	(	string	originalName,
		string	newName
	)

Rename a variable in all nested expressions.

Parameters:

originalName	The name of the variable to rename
newName	The new name to replace the original variable name

void RAIN.Belief.ConditionalExpression.SetExpression	(	Expression	expr1,
		ComparisonType	comparisonOperator,
		Expression	expr2
	)

Reset the ConditionalExpression with a new rhs, operator, and lhs.

Parameters:

expr1	The left-hand-side expression
comparisonOperator	The comparison operator
expr2	The right-hand-side expression

void RAIN.Belief.ConditionalExpression.SetInvalid

(

)

Invalidate the ConditionalExpression.

override string RAIN.Belief.ConditionalExpression.ToString

(

)

ToString() will return a string representation of the ConditionalExpression which may differ from the original text parsed to create this expression.

Returns:

Returns a text representation of the ConditionalExpressoin

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Property Documentation

string RAIN.Belief.ConditionalExpression.ExpressionAsEntered [get, set]

ExpressionAsEntered returns the text used to initially describe the ConditionalExpression, if the expression was created from parsing a script or manual entry. This is useful when supporting user editing of invalid expressions.

bool RAIN.Belief.ConditionalExpression.IsValid [get]

Is the conditional expression valid and can it be evaluated successfully? Checks to ensure that the Conditional Expression is formed of valid lhs and rhs expressions, and that the comparison operator is not a no-op.