[Properties (by Name)] [Methods (by Name)] [Events (by Name)]
Class for parsing and evaluating mathematical expressions
Source position: fpexprpars.pp line 726
type TFPExpressionParser = class(TComponent) |
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public |
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constructor Create(); override; |
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Create expression parser instance |
destructor Destroy; override; |
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Destroy expression parser and free resources |
function IdentifierByName(); virtual; |
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Get identifier definition by name |
procedure Clear; |
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Clear the current expression |
procedure EvaluateExpression(); |
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Evaluate the expression and return result |
procedure ExtractIdentifierNames(); |
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function ExtractNode(); |
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Extract expression node from result |
function Evaluate; |
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Evaluate the current expression |
function ResultType; |
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Get the result type of the expression |
function HasAggregate; |
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Check if expression contains aggregates |
procedure InitAggregate; |
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Initialize aggregate calculation |
procedure UpdateAggregate; |
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Update aggregate calculation with value |
property AsFloat: TExprFloat; [r] |
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Expression result as floating point value |
property AsCurrency: Currency; [r] |
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Expression result as currency value |
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Expression result as integer value |
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property AsString: AnsiString; [r] |
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Expression result as string value |
property AsBoolean: Boolean; [r] |
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Expression result as boolean value |
property AsDateTime: TDateTime; [r] |
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Expression result as date/time value |
published |
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property Expression: Ansistring; [rw] |
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Expression string to be evaluated |
property Identifiers: TFPExprIdentifierDefs; [rw] |
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Collection of identifiers and their values |
property BuiltIns: TBuiltInCategories; [rw] |
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Manager for built-in functions and constants |
end; |
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Class for parsing and evaluating mathematical expressions |
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This is the main expression parser class that provides comprehensive functionality for parsing and evaluating mathematical expressions.
The parser handles the complete expression evaluation pipeline from tokenization through parsing to evaluation, supporting complex expressions with proper operator precedence, parentheses, function calls, and variable references.
Key features include built-in mathematical functions, string operations, date/time handling, boolean logic, comparison operations, and extensibility through custom functions and variables.
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Class for managing built-in functions and variables in expressions |