Package com.blackrook.rookscript.struct

Class PreprocessorLexer

java.lang.Object

com.blackrook.rookscript.struct.Lexer

com.blackrook.rookscript.struct.PreprocessorLexer

Direct Known Subclasses:

ScriptLexer

public class PreprocessorLexer
extends Lexer

A lexer that scans for specific directives and affects the stream.

• #include "file path" - Pushes a file onto the stream stack.
• #define MACRO ...tokens... - Defines a macro and the string to replace them with. Defines are case-insensitive.
• #undefine MACRO - Undefines a macro.
• #ifdef MACRO - Includes the next set of lines (until #endif) if the provided macro is defined.
• #ifndef MACRO - Includes the next set of lines (until #endif) if the provided macro is NOT defined.
• #endif - Ends an "if" directive block.
• #else - Block that is used if an "if" block does not succeed.

Author:

Matthew Tropiano

See Also:

• Lexer

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PreprocessorLexer.DefaultIncluder	Default includer to use when none specified.
static interface	PreprocessorLexer.Includer	An interface that allows the user to resolve a resource by path when the PreprocessorLexer parses it.
static class	PreprocessorLexer.PreprocessorException	Thrown on preprocessor error.
static interface	PreprocessorLexer.StringProvider	Lambda interface that returns a string.

Nested classes/interfaces inherited from class com.blackrook.rookscript.struct.Lexer

Lexer.Kernel, Lexer.Parser, Lexer.ReaderStack, Lexer.Token

Field Summary

Fields

Modifier and Type	Field	Description
static final PreprocessorLexer.DefaultIncluder	DEFAULT_INCLUDER	The singular instance for the default includer.
static final String	DIRECTIVE_BANG	Preprocessor directive - Bang.
static final String	DIRECTIVE_DEFINE	Preprocessor directive - Define.
static final String	DIRECTIVE_ELSE	Preprocessor directive - Else.
static final String	DIRECTIVE_ENDIF	Preprocessor directive - End If.
static final String	DIRECTIVE_IFDEF	Preprocessor directive - If Defined.
static final String	DIRECTIVE_IFNDEF	Preprocessor directive - If Undefined.
static final String	DIRECTIVE_INCLUDE	Preprocessor directive - Include.
static final String	DIRECTIVE_UNDEFINE	Preprocessor directive - Undefine.

Fields inherited from class com.blackrook.rookscript.struct.Lexer

DEBUG, END_OF_LEXER, END_OF_STREAM, NEWLINE

Constructor Summary

Constructors

Constructor	Description
PreprocessorLexer(Lexer.Kernel kernel, Reader in)	Creates a new preprocessor lexer around a reader.
PreprocessorLexer(Lexer.Kernel kernel, String in)	Creates a new preprocessor lexer around a String, that will be wrapped into a StringReader.
PreprocessorLexer(Lexer.Kernel kernel, String name, Reader in)	Creates a new preprocessor lexer around a reader.
PreprocessorLexer(Lexer.Kernel kernel, String name, String in)	Creates a new preprocessor lexer around a String, that will be wrapped into a StringReader.

Method Summary

Modifier and Type	Method	Description
void	addDefine(String macro, PreprocessorLexer.StringProvider tokenProvider)	Adds a define macro to this lexer.
void	addDefine(String macro, String tokenString)	Adds a define macro to this lexer.
protected String	getInfoLine(String streamName, int lineNumber, String token, String message)
Lexer.Token	nextToken()	Gets the next token.
protected void	preprocess()
protected void	processDirectiveLine(String streamName, int lineNumber, String directiveLine)	Called when a full directive is read and needs to be processed.
protected char	readChar()	Reads a character from the stream.
void	setIncluder(PreprocessorLexer.Includer includer)	Sets the primary includer to use for resolving included streams.

Methods inherited from class com.blackrook.rookscript.struct.Lexer

clearCurrentLexeme, getCurrentLexeme, getCurrentLineNumber, getCurrentStream, getCurrentStreamName, getRawStringEnd, getState, getStringEnd, isCommentEndDelimiterStart, isDelimiterStart, isDigit, isExponent, isExponentSign, isHexDigit, isLetter, isLexerEnd, isNewline, isPoint, isRawStringStart, isSpace, isStreamEnd, isStringEnd, isStringEscape, isStringStart, isTab, isUnderscore, isWhitespace, modifyType, pushStream, saveChar, setDelimBreak, setMultilineStringStartAndEnd, setState, setStringStartAndEnd

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DIRECTIVE_BANG

public static final String DIRECTIVE_BANG

Preprocessor directive - Bang.

See Also:

• Constant Field Values

DIRECTIVE_INCLUDE

public static final String DIRECTIVE_INCLUDE

Preprocessor directive - Include.

See Also:

• Constant Field Values

DIRECTIVE_DEFINE

public static final String DIRECTIVE_DEFINE

Preprocessor directive - Define.

See Also:

• Constant Field Values

DIRECTIVE_UNDEFINE

public static final String DIRECTIVE_UNDEFINE

Preprocessor directive - Undefine.

See Also:

• Constant Field Values

DIRECTIVE_IFDEF

public static final String DIRECTIVE_IFDEF

Preprocessor directive - If Defined.

See Also:

• Constant Field Values

DIRECTIVE_IFNDEF

public static final String DIRECTIVE_IFNDEF

Preprocessor directive - If Undefined.

See Also:

• Constant Field Values

DIRECTIVE_ENDIF

public static final String DIRECTIVE_ENDIF

Preprocessor directive - End If.

See Also:

• Constant Field Values

DIRECTIVE_ELSE

public static final String DIRECTIVE_ELSE

Preprocessor directive - Else.

See Also:

• Constant Field Values

DEFAULT_INCLUDER

public static final PreprocessorLexer.DefaultIncluder DEFAULT_INCLUDER

The singular instance for the default includer.

Constructor Details

PreprocessorLexer

public PreprocessorLexer(Lexer.Kernel kernel,
 String in)

Creates a new preprocessor lexer around a String, that will be wrapped into a StringReader. This will also assign this lexer a default name.

Parameters:

kernel - the lexer kernel to use for defining how to parse the input text.

in - the string to read from.

PreprocessorLexer

public PreprocessorLexer(Lexer.Kernel kernel,
 String name,
 String in)

Creates a new preprocessor lexer around a String, that will be wrapped into a StringReader.

Parameters:

kernel - the lexer kernel to use for defining how to parse the input text.

name - the name of this lexer.

in - the reader to read from.

PreprocessorLexer

public PreprocessorLexer(Lexer.Kernel kernel,
 Reader in)

Creates a new preprocessor lexer around a reader. This will also assign this lexer a default name.

Parameters:

kernel - the kernel to use for this lexer.

in - the reader to read from.

PreprocessorLexer

public PreprocessorLexer(Lexer.Kernel kernel,
 String name,
 Reader in)

Creates a new preprocessor lexer around a reader.

Parameters:

kernel - the kernel to use for this lexer.

name - the name of this lexer.

in - the reader to read from.

Method Details

setIncluder

public void setIncluder(PreprocessorLexer.Includer includer)

Sets the primary includer to use for resolving included streams.

Parameters:

includer - the includer to use.

addDefine

public void addDefine(String macro,
 String tokenString)

Adds a define macro to this lexer.

Parameters:

macro - the macro identifier.

tokenString - the string to push onto the lexer.

addDefine

public void addDefine(String macro,
 PreprocessorLexer.StringProvider tokenProvider)

Adds a define macro to this lexer.

Parameters:

macro - the macro identifier.

tokenProvider - a string-producing lambda function.

nextToken

public Lexer.Token nextToken()
                      throws IOException

Description copied from class: Lexer

Gets the next token. If there are no tokens left to read, this will return null. This method is NOT thread-safe!

Overrides:

nextToken in class Lexer

Returns:

the next token, or null if no more tokens to read.

Throws:

IOException - if a token cannot be read by the underlying Reader.

getInfoLine

protected String getInfoLine(String streamName,
 int lineNumber,
 String token,
 String message)

readChar

protected char readChar()
                 throws IOException

Description copied from class: Lexer

Reads a character from the stream.

Overrides:

readChar in class Lexer

Returns:

the character read, or Lexer.END_OF_LEXER if no more characters, or Lexer.END_OF_STREAM if end of current stream.

Throws:

IOException - if a character cannot be read.

preprocess

protected void preprocess()
                   throws IOException

Throws:

IOException

processDirectiveLine

protected void processDirectiveLine(String streamName,
 int lineNumber,
 String directiveLine)

Called when a full directive is read and needs to be processed.

Parameters:

streamName - the stream name.

lineNumber - the line number.

directiveLine - the directive line to process.