java.lang.Object
- com.blackrook.archetext.struct.Lexer
- - com.blackrook.archetext.struct.PreprocessorLexer

```
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.archetext.struct.Lexer
Lexer.Kernel, Lexer.Parser, Lexer.ReaderStack, Lexer.Token

Field Summary

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

Fields inherited from class com.blackrook.archetext.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

All Methods Instance Methods Concrete Methods
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.archetext.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 Detail
  - 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 Detail
  - 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 Detail
  - 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.

Class PreprocessorLexer

Nested Class Summary

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

Field Summary

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

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

Field Detail

DIRECTIVE_BANG

DIRECTIVE_INCLUDE

DIRECTIVE_DEFINE

DIRECTIVE_UNDEFINE

DIRECTIVE_IFDEF

DIRECTIVE_IFNDEF

DIRECTIVE_ENDIF

DIRECTIVE_ELSE

DEFAULT_INCLUDER

Constructor Detail

PreprocessorLexer

PreprocessorLexer

PreprocessorLexer

PreprocessorLexer

Method Detail

setIncluder

addDefine

addDefine

nextToken

getInfoLine

readChar

preprocess

processDirectiveLine