TFPExpressionScanner class

In unit fpExprPars

Class for tokenizing expression strings into parser tokens

Declaration

pascal

TFPExpressionScanner = class(TObject)

Inheritance

TFPExpressionScanner
TObject

Description

The TFPExpressionScanner class performs lexical analysis on expression strings, breaking them into tokens that can be consumed by the expression parser. It handles the low-level details of character recognition, string parsing, and token classification.

The scanner recognizes all token types defined in TTokenType including operators, literals, identifiers, keywords, and delimiters.

Properties

`Token`	public	The text of the current token
`TokenType`	public	The type of the current token
`Source`	public	The source expression string to scan
`Pos`	public	Current position in the source string
`CurrentChar`	public	The current character being processed

Methods

`SetSource`	protected
`DoIdentifier`	protected
`DoNumber`	protected
`DoDelimiter`	protected
`DoString`	protected
`NextPos`	protected
`SkipWhiteSpace`	protected
`IsWordDelim`	protected
`IsDelim`	protected
`IsDigit`	protected
`IsAlpha`	protected
`Create`	public	Create a new expression scanner
`GetToken`	public	Get the next token from the source expression

Fields

`FSource`
`LSource`
`FPos`
`FChar`
`FToken`
`FTokenType`

Inherited

From TObject (41)

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An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.