Package antlr

Class PythonCodeGenerator

java.lang.Object
antlr.CodeGenerator
antlr.PythonCodeGenerator
public class PythonCodeGenerator extends CodeGenerator
Generate MyParser.java, MyLexer.java and MyParserTokenTypes.java

  • Field Details

    • syntacticPredLevel

      protected int syntacticPredLevel

    • genAST

      protected boolean genAST

    • saveText

      protected boolean saveText

    • labeledElementType

      String labeledElementType

    • labeledElementASTType

      String labeledElementASTType

    • labeledElementInit

      String labeledElementInit

    • commonExtraArgs

      String commonExtraArgs

    • commonExtraParams

      String commonExtraParams

    • commonLocalVars

      String commonLocalVars

    • lt1Value

      String lt1Value

    • exceptionThrown

      String exceptionThrown

    • throwNoViable

      String throwNoViable

    • initHeaderAction

      public static final String initHeaderAction
      See Also:

    • mainHeaderAction

      public static final String mainHeaderAction
      See Also:

    • lexerClassName

      String lexerClassName

    • parserClassName

      String parserClassName

    • treeWalkerClassName

      String treeWalkerClassName

    • currentRule

      RuleBlock currentRule
      Tracks the rule being generated. Used for mapTreeId

    • currentASTResult

      String currentASTResult
      Tracks the rule or labeled subrule being generated. Used for AST generation.

    • treeVariableMap

      Hashtable treeVariableMap
      Mapping between the ids used in the current alt, and the names of variables used to represent their AST values.

    • declaredASTVariables

      Hashtable declaredASTVariables
      Used to keep track of which AST variables have been defined in a rule (except for the #rule_name and #rule_name_in var's

    • astVarNumber

      int astVarNumber

    • NONUNIQUE

      protected static final String NONUNIQUE
      Special value used to mark duplicate in treeVariableMap

    • caseSizeThreshold

      public static final int caseSizeThreshold
      See Also:

  • Constructor Details

    • PythonCodeGenerator

      public PythonCodeGenerator()

  • Method Details

    • printTabs

      protected void printTabs()
      Create a Java code-generator using the given Grammar. The caller must still call setTool, setBehavior, and setAnalyzer before generating code.
      Overrides:
      printTabs in class CodeGenerator

    • addSemPred

      protected int addSemPred(String predicate)
      Adds a semantic predicate string to the sem pred vector These strings will be used to build an array of sem pred names when building a debugging parser. This method should only be called when the debug option is specified

    • exitIfError

      public void exitIfError()

    • checkCurrentOutputStream

      protected void checkCurrentOutputStream()

    • extractIdOfAction

      protected String extractIdOfAction(String s, int line, int column)
      Get the identifier portion of an argument-action. For Python the ID of an action is assumed to be everything before the assignment, as Python does not support a type.
      Overrides:
      extractIdOfAction in class CodeGenerator
      Parameters:
      s - The action text
      line - Line used for error reporting.
      column - Line used for error reporting.
      Returns:
      A string containing the text of the identifier

    • extractTypeOfAction

      protected String extractTypeOfAction(String s, int line, int column)
      Get the type portion of an argument-action. Python does not have a type declaration before an identifier, so we just return the empty string.
      Overrides:
      extractTypeOfAction in class CodeGenerator
      Parameters:
      s - The action text
      line - Line used for error reporting.
      Returns:
      A string containing the text of the type

    • flushTokens

      protected void flushTokens()

    • gen

      public void gen()
      Generate the parser, lexer, treeparser, and token types in Java
      Specified by:
      gen in class CodeGenerator

    • gen

      public void gen(ActionElement action)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      action - The {...} action to generate
      blk - The {...} action to generate

    • gen

      public void gen(AlternativeBlock blk)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      blk - The "x|y|z|..." block to generate

    • gen

      public void gen(BlockEndElement end)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      end - The block-end element to generate. Block-end elements are synthesized by the grammar parser to represent the end of a block.
      blk - The block-end element to generate. Block-end elements are synthesized by the grammar parser to represent the end of a block.

    • gen

      public void gen(CharLiteralElement atom)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      atom - The character literal reference to generate
      blk - The character literal reference to generate

    • toString

      String toString(boolean v)

    • gen

      public void gen(CharRangeElement r)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      r - The character-range reference to generate
      blk - The character-range reference to generate

    • gen

      public void gen(LexerGrammar g) throws IOException
      Generate the lexer Java file
      Specified by:
      gen in class CodeGenerator
      Throws:
      IOException

    • genHeaderMain

      protected void genHeaderMain(Grammar grammar)

    • genHeaderInit

      protected void genHeaderInit(Grammar grammar)

    • printMainFunc

      protected void printMainFunc(String s)

    • gen

      public void gen(OneOrMoreBlock blk)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      blk - The (...)+ block to generate

    • gen

      public void gen(ParserGrammar g) throws IOException
      Generate the parser Java file
      Specified by:
      gen in class CodeGenerator
      Throws:
      IOException

    • gen

      public void gen(RuleRefElement rr)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      rr - The rule-reference to generate
      blk - The rule-reference to generate

    • gen

      public void gen(StringLiteralElement atom)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      atom - The string-literal reference to generate
      blk - The string-literal reference to generate

    • gen

      public void gen(TokenRangeElement r)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      r - The token-range reference to generate
      blk - The token-range reference to generate

    • gen

      public void gen(TokenRefElement atom)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      atom - The token-reference to generate
      blk - The token-reference to generate

    • gen

      public void gen(TreeElement t)
      Description copied from class: CodeGenerator
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator

    • gen

      public void gen(TreeWalkerGrammar g) throws IOException
      Generate the tree-parser Java file
      Specified by:
      gen in class CodeGenerator
      Throws:
      IOException

    • gen

      public void gen(WildcardElement wc)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      wc - The wildcard element to generate

    • gen

      public void gen(ZeroOrMoreBlock blk)
      Generate code for the given grammar element.
      Specified by:
      gen in class CodeGenerator
      Parameters:
      blk - The (...)* block to generate

    • genAlt

      protected void genAlt(Alternative alt, AlternativeBlock blk)
      Generate an alternative.
      Parameters:
      alt - The alternative to generate
      blk - The block to which the alternative belongs

    • genBitsets

      protected void genBitsets(Vector bitsetList, int maxVocabulary)
      Generate all the bitsets to be used in the parser or lexer Generate the raw bitset data like "long _tokenSet1_data[] = {...}" and the BitSet object declarations like "BitSet _tokenSet1 = new BitSet(_tokenSet1_data)" Note that most languages do not support object initialization inside a class definition, so other code-generators may have to separate the bitset declarations from the initializations (e.g., put the initializations in the generated constructor instead).
      Parameters:
      bitsetList - The list of bitsets to generate.
      maxVocabulary - Ensure that each generated bitset can contain at least this value.

    • genBlockInitAction

      protected void genBlockInitAction(AlternativeBlock blk)
      Generate the init action for a block, which may be a RuleBlock or a plain AlternativeBLock.

    • genBlockPreamble

      protected void genBlockPreamble(AlternativeBlock blk)
      Generate the header for a block, which may be a RuleBlock or a plain AlternativeBLock. This generates any variable declarations and syntactic-predicate-testing variables.

    • genCases

      protected void genCases(BitSet p)
      Generate a series of case statements that implement a BitSet test.
      Parameters:
      p - The Bitset for which cases are to be generated

    • genCommonBlock

      public PythonBlockFinishingInfo genCommonBlock(AlternativeBlock blk, boolean noTestForSingle)
      Generate common code for a block of alternatives; return a postscript that needs to be generated at the end of the block. Other routines may append else-clauses and such for error checking before the postfix is generated. If the grammar is a lexer, then generate alternatives in an order where alternatives requiring deeper lookahead are generated first, and EOF in the lookahead set reduces the depth of the lookahead. @param blk The block to generate @param noTestForSingle If true, then it does not generate a test for a single alternative.

    • genASTDeclaration

      protected void genASTDeclaration(AlternativeElement el)

    • genASTDeclaration

      protected void genASTDeclaration(AlternativeElement el, String node_type)

    • genASTDeclaration

      protected void genASTDeclaration(AlternativeElement el, String var_name, String node_type)

    • genHeader

      protected void genHeader()
      Generate a header that is common to all Python files

    • genLexerTest

      protected void genLexerTest()
      Generate an automated test for Python CharScanner (sub)classes.

    • genMatch

      protected void genMatch(BitSet b)

    • genMatch

      protected void genMatch(GrammarAtom atom)

    • genMatchUsingAtomText

      protected void genMatchUsingAtomText(GrammarAtom atom)

    • genMatchUsingAtomTokenType

      protected void genMatchUsingAtomTokenType(GrammarAtom atom)

    • genNextToken

      public void genNextToken()
      Generate the nextToken() rule. nextToken() is a synthetic lexer rule that is the implicit OR of all user-defined lexer rules.

    • genRule

      public void genRule(RuleSymbol s, boolean startSymbol, int ruleNum)
      Gen a named rule block. ASTs are generated for each element of an alternative unless the rule or the alternative have a '!' modifier. If an alternative defeats the default tree construction, it must set _AST to the root of the returned AST. Each alternative that does automatic tree construction, builds up root and child list pointers in an ASTPair structure. A rule finishes by setting the returnAST variable from the ASTPair.
      Parameters:
      startSymbol - true if the rule is a start symbol (i.e., not referenced elsewhere)
      rule - The name of the rule to generate

    • genSemPred

      protected void genSemPred(String pred, int line)

    • genSemPredMap

      protected void genSemPredMap()
      Write an array of Strings which are the semantic predicate expressions. The debugger will reference them by number only

    • genSynPred

      protected void genSynPred(SynPredBlock blk, String lookaheadExpr)

    • genTokenStrings

      public void genTokenStrings()
      Generate a static array containing the names of the tokens, indexed by the token type values. This static array is used to format error messages so that the token identifers or literal strings are displayed instead of the token numbers. If a lexical rule has a paraphrase, use it rather than the token label.

    • genTokenASTNodeMap

      protected void genTokenASTNodeMap()
      Create and set Integer token type objects that map to Java Class objects (which AST node to create).

    • genTokenTypes

      protected void genTokenTypes(TokenManager tm) throws IOException
      Generate the token types Java file
      Throws:
      IOException

    • getASTCreateString

      public String getASTCreateString(Vector v)
      Get a string for an expression to generate creation of an AST subtree.
      Specified by:
      getASTCreateString in class CodeGenerator
      Parameters:
      v - A Vector of String, where each element is an expression in the target language yielding an AST node.

    • getASTCreateString

      public String getASTCreateString(GrammarAtom atom, String astCtorArgs)
      Get a string for an expression to generate creating of an AST node
      Specified by:
      getASTCreateString in class CodeGenerator
      Parameters:
      atom - The grammar node for which you are creating the node
      astCtorArgs - The text of the arguments to the AST construction
      str - The arguments to the AST constructor

    • getASTCreateString

      public String getASTCreateString(String astCtorArgs)
      Get a string for an expression to generate creating of an AST node. Parse the first (possibly only) argument looking for the token type. If the token type is a valid token symbol, ask for it's AST node type and add to the end if only 2 arguments. The forms are #[T], #[T,"t"], and as of 2.7.2 #[T,"t",ASTclassname].
      Parameters:
      str - The arguments to the AST constructor

    • getLookaheadTestExpression

      protected String getLookaheadTestExpression(Lookahead[] look, int k)

    • getLookaheadTestExpression

      protected String getLookaheadTestExpression(Alternative alt, int maxDepth)
      Generate a lookahead test expression for an alternate. This will be a series of tests joined by 'invalid input: '&'invalid input: '&'' and enclosed by '()', the number of such tests being determined by the depth of the lookahead.

    • getLookaheadTestTerm

      protected String getLookaheadTestTerm(int k, BitSet p)
      Generate a depth==1 lookahead test expression given the BitSet. This may be one of: 1) a series of 'x==X||' tests 2) a range test using >= invalid input: '&'invalid input: '&' invalid input: '<'= where possible, 3) a bitset membership test for complex comparisons
      Parameters:
      k - The lookahead level
      p - The lookahead set for level k

    • getRangeExpression

      public String getRangeExpression(int k, int[] elems)
      Return an expression for testing a contiguous renage of elements
      Parameters:
      k - The lookahead level
      elems - The elements representing the set, usually from BitSet.toArray().
      Returns:
      String containing test expression.

    • lookaheadIsEmpty

      protected boolean lookaheadIsEmpty(Alternative alt, int maxDepth)
      Is the lookahead for this alt empty?

    • mapTreeId

      public String mapTreeId(String idParam, ActionTransInfo transInfo)
      Map an identifier to it's corresponding tree-node variable. This is context-sensitive, depending on the rule and alternative being generated
      Specified by:
      mapTreeId in class CodeGenerator
      Parameters:
      idParam - The identifier name to map
      Returns:
      The mapped id (which may be the same as the input), or null if the mapping is invalid due to duplicates

    • processActionForSpecialSymbols

      protected String processActionForSpecialSymbols(String actionStr, int line, RuleBlock currentRule, ActionTransInfo tInfo)
      Lexically process $var and tree-specifiers in the action. This will replace #id and #(...) with the appropriate function calls and/or variables etc...
      Specified by:
      processActionForSpecialSymbols in class CodeGenerator

    • isEmpty

      static boolean isEmpty(String s)

    • processActionCode

      protected String processActionCode(String actionStr, int line)

    • printActionCode

      protected void printActionCode(String actionStr, int line)

    • setupOutput

      public void setupOutput(String className) throws IOException
      This method exists so a subclass, namely VAJCodeGenerator, can open the file in its own evil way. JavaCodeGenerator simply opens a text file...
      Throws:
      IOException

    • isspace

      protected boolean isspace(char c)

    • _printAction

      protected void _printAction(String s)
      Description copied from class: CodeGenerator
      Print an action without leading tabs, attempting to preserve the current indentation level for multi-line actions Ignored if string is null.
      Overrides:
      _printAction in class CodeGenerator
      Parameters:
      s - The action string to output

    • od

      protected void od(String s, int i, int end, String msg)

    • printAction

      protected void printAction(String s)
      Description copied from class: CodeGenerator
      Print an action with leading tabs, attempting to preserve the current indentation level for multi-line actions Ignored if string is null.
      Overrides:
      printAction in class CodeGenerator
      Parameters:
      s - The action string to output

    • printGrammarAction

      protected void printGrammarAction(Grammar grammar)

    • _printJavadoc

      protected void _printJavadoc(String s)

    • genJavadocComment

      protected void genJavadocComment(Grammar g)

    • genJavadocComment

      protected void genJavadocComment(RuleSymbol g)