step9
Class expr

java.lang.Object
  step9.expr

public class expr
extends Object

fairly comprehensive mixed mode expressions on lines.

Nested Class Summary

static interface	expr.yyActions interface between grammar and actions.
static class	expr.yyException thrown for irrecoverable syntax errors and stack overflow.
static interface	expr.yyInput must be implemented by a scanner object to supply input to the parser.
static class	expr.yyLex
static class	expr.yyTree tree factory.

Field Summary

static int	_0
static int	_1
static int	_2
static int	_3
static int	_4
static int	_5
static int	_6
static int	_7
static int	Bool
static int	Int
static int	Real
static int	Text
protected expr.yyActions	yyAct current factory.
protected static short[]	yyCheck parser tables.
protected static short[]	yyDefRed parser tables.
protected static short[]	yyDgoto parser tables.
static int	yyErrorCode
protected static int	yyFinal number of final state.
protected static short[]	yyGindex parser tables.
protected static short[]	yyLen parser tables.
protected static short[]	yyLhs parser tables.
protected int	yyMax initial size and increment of the state/value stack [default 256].
protected static String[]	yyNames maps symbol value to printable name.
protected static short[]	yyRindex parser tables.
protected static short[]	yySindex parser tables.
protected static short[]	yyTable parser tables.

Constructor Summary

expr()

Method Summary

static void	main(String[] args) main program to test parser and tree factory.
protected Object	yyDefault(Object first) executed at the beginning of a reduce action.
void	yyerror(String message) simplified error message.
void	yyerror(String message, String[] expected) (syntax) error message.
protected String[]	yyExpecting(int state) computes list of expected tokens on error by tracing the tables.
Object	yyparse(expr.yyInput yyLex) the generated parser.
Object	yyparse(expr.yyInput yyLex, expr.yyActions yyAct) entry point for parser without trace.
Object	yyparse(expr.yyInput yyLex, Object yydebug) the generated parser, with debugging messages.
Object	yyparse(expr.yyInput yyLex, Object yydebug, expr.yyActions yyAct) entry point for parser with trace.

Methods inherited from class java.lang.Object

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

Field Detail

yyAct

protected expr.yyActions yyAct

current factory.

Bool

public static final int Bool

See Also:

Constant Field Values

Int

public static final int Int

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Constant Field Values

Real

public static final int Real

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Constant Field Values

Text

public static final int Text

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Constant Field Values

_0

public static final int _0

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Constant Field Values

_1

public static final int _1

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Constant Field Values

_2

public static final int _2

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Constant Field Values

_3

public static final int _3

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Constant Field Values

_4

public static final int _4

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Constant Field Values

_5

public static final int _5

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Constant Field Values

_6

public static final int _6

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Constant Field Values

_7

public static final int _7

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Constant Field Values

yyErrorCode

public static final int yyErrorCode

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Constant Field Values

yyFinal

protected static final int yyFinal

number of final state.

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Constant Field Values

yyLhs

protected static final short[] yyLhs

parser tables. Order is mandated by jay.

yyLen

protected static final short[] yyLen

parser tables. Order is mandated by jay.

yyDefRed

protected static final short[] yyDefRed

parser tables. Order is mandated by jay.

yyDgoto

protected static final short[] yyDgoto

parser tables. Order is mandated by jay.

yySindex

protected static final short[] yySindex

parser tables. Order is mandated by jay.

yyRindex

protected static final short[] yyRindex

parser tables. Order is mandated by jay.

yyGindex

protected static final short[] yyGindex

parser tables. Order is mandated by jay.

yyTable

protected static final short[] yyTable

parser tables. Order is mandated by jay.

yyCheck

protected static final short[] yyCheck

parser tables. Order is mandated by jay.

yyNames

protected static final String[] yyNames

maps symbol value to printable name.

See Also:

yyExpecting(int)

yyMax

protected int yyMax

initial size and increment of the state/value stack [default 256]. This is not final so that it can be overwritten outside of invocations of yyparse(step9.expr.yyInput, java.lang.Object, step9.expr.yyActions).

Constructor Detail

expr

public expr()

Method Detail

yyparse

public Object yyparse(expr.yyInput yyLex,
                      Object yydebug,
                      expr.yyActions yyAct)
               throws IOException,
                      expr.yyException

entry point for parser with trace.

Throws:

IOException

expr.yyException

yyparse

public Object yyparse(expr.yyInput yyLex,
                      expr.yyActions yyAct)
               throws IOException,
                      expr.yyException

entry point for parser without trace.

Throws:

IOException

expr.yyException

yyerror

public void yyerror(String message)

simplified error message.

See Also:

yyerror(java.lang.String, java.lang.String[])

yyerror

public void yyerror(String message,
                    String[] expected)

(syntax) error message. Can be overwritten to control message format.

Parameters:

message - text to be displayed.

expected - list of acceptable tokens, if available.

yyExpecting

protected String[] yyExpecting(int state)

computes list of expected tokens on error by tracing the tables.

Parameters:

state - for which to compute the list.

Returns:

list of token names.

yyparse

public Object yyparse(expr.yyInput yyLex,
                      Object yydebug)
               throws IOException,
                      expr.yyException

the generated parser, with debugging messages. Maintains a dynamic state and value stack.

Parameters:

yyLex - scanner.

yydebug - debug message writer implementing yyDebug, or null.

Returns:

result of the last reduction, if any.

Throws:

expr.yyException - on irrecoverable parse error.

IOException

yyDefault

protected Object yyDefault(Object first)

executed at the beginning of a reduce action. Used as $$ = yyDefault($1), prior to the user-specified action, if any. Can be overwritten to provide deep copy, etc.

Parameters:

first - value for $1, or null.

Returns:

first.

yyparse

public Object yyparse(expr.yyInput yyLex)
               throws IOException,
                      expr.yyException

the generated parser. Maintains a dynamic state and value stack.

Parameters:

yyLex - scanner.

Returns:

result of the last reduction, if any.

Throws:

expr.yyException - on irrecoverable parse error.

IOException

main

public static void main(String[] args)
                 throws expr.yyException,
                        IOException

main program to test parser and tree factory. static scanner.

Throws:

expr.yyException

IOException