stanhebben.zenscript.parser

Class NFA

java.lang.Object

stanhebben.zenscript.parser.NFA

public class NFA
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	NFA.NFAState Represents an NFA state.

Field Summary

Fields

Modifier and Type	Field and Description
static int	EPSILON
static int	NOFINAL
static int	UNICODE_ESCAPE

Constructor Summary

Constructors

Constructor and Description
NFA(NFA.NFAState initial) Creates a new NFA with the specified initial state.
NFA(java.lang.String regexp) Creates a new NFA from the specified regular expression.
NFA(java.lang.String[] regexp, int[] finals) Converts an array of regular expressions to an NFA.

Method Summary

Modifier and Type	Method and Description
DFA	toDFA() Converts this NFA to a DFA.

Methods inherited from class java.lang.Object

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

Field Detail

NOFINAL

public static final int NOFINAL

See Also:

Constant Field Values

EPSILON

public static final int EPSILON

See Also:

Constant Field Values

UNICODE_ESCAPE

public static final int UNICODE_ESCAPE

See Also:

Constant Field Values

Constructor Detail

NFA

public NFA(NFA.NFAState initial)

Creates a new NFA with the specified initial state.

Parameters:

initial - initial state

NFA

public NFA(java.lang.String regexp)

Creates a new NFA from the specified regular expression.

Note: the regular expression implementation is not complete. Shorthand character classes (\s, \w, \d), hexadecimal and unicode escape sequences and unicode properties are not implemented.

Anchors, lazy plus operators, lookbehind and lookforward are not implemented since they cannot be implemented in an NFA.

Parameters:

regexp - regular expression

NFA

public NFA(java.lang.String[] regexp,
           int[] finals)

Converts an array of regular expressions to an NFA. Each regular expression can have its own final class. The length of both arrays must match.

Parameters:

regexp - regular expression array

finals - final classes

Method Detail

toDFA

public DFA toDFA()

Converts this NFA to a DFA. The resulting DFA is not optimal. If the NFA is ambiguous, the token with lowest value will receive preference.

Returns:

this NFA as DFA