Expression (WoolCore 1.0.2 API)

All Known Implementing Classes:

AddExpression, AndExpression, AssignExpression, DivideExpression, DotExpression, EqualExpression, GreaterEqualExpression, GreaterThanExpression, GroupExpression, IndexExpression, InExpression, LessEqualExpression, LessThanExpression, ListExpression, MultiplyExpression, NotEqualExpression, NotExpression, NotStrictEqualExpression, ObjectExpression, OrExpression, StrictEqualExpression, StringExpression, SubtractExpression, ValueExpression
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public interface Expression
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An expression is some code that can be evaluated as a Value. Instances can be obtained from text input using the ExpressionParser. It has one method: evaluate(), which takes a map of variables. The expression may contain variable names and their values will be taken from the map. A variable name that is not included in the map, will be evaluated as null. The variable values should be the same elementary types as in Value. That is one of the following:
- null
- String
- Number
- Boolean
- List
- Map: the keys must be strings
Each element of a list or map should also be one of these types.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Value`	`evaluate(Map<String,Object> variables)`	Evaluates this expression using the specified variable values.
`List<Expression>`	`getChildren()`	Returns the child expressions of this expression.
`List<Expression>`	`getDescendants()`	Returns all descendant expressions of this expression.
`Set<String>`	`getVariableNames()`	Returns all variable names that occur in this expression and its descendants.

- Method Detail
  - evaluate
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Value evaluate(Map<String,Object> variables)
        throws EvaluationException
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    Evaluates this expression using the specified variable values. The variable map may be modified as a result of an "assign" expression.
    
    Parameters:
    
    variables - the variable values (can be null)
    
    Returns:
    
    the value of the expression
    
    Throws:
    
    EvaluationException - if the expression can't be evaluted with the specified variables
  - getChildren
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List<Expression> getChildren()
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    Returns the child expressions of this expression.
    
    Returns:
    
    the child expressions
  - getDescendants
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List<Expression> getDescendants()
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    Returns all descendant expressions of this expression.
    
    Returns:
    
    the descendant expressions
  - getVariableNames
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Set<String> getVariableNames()
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    Returns all variable names that occur in this expression and its descendants.
    
    Returns:
    
    the variable names