Package jflex.core
Class RegExp
java.lang.Object
jflex.core.RegExp
Stores a regular expression of rules section in a JFlex-specification.
This base class has no content other than its type.
- Version:
- JFlex 1.8.2
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Field Summary
Fields -
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionstatic RegExp
anyChar()
Returns a regexp that matches any character:[^]
static RegExp1
Confirms that the parameter is a RegExp1 of type sym.PRIMCLASS.boolean
Find out if this regexp is a char class or equivalent to one.final void
makeCCLs
(CharClasses c, boolean caseless) Make character class partitions based on the classes mentioned in this regexp.final RegExp
Normalise the regular expression to eliminate macro use (expand them), and compound character class expression (compute their content).static IntCharSet
performClassOp
(int op, IntCharSet l, IntCharSet r, RegExp ctxt) Performs the given set operation on the twoIntCharSet
parameters.Returns a String-representation of this regular expression with the specified indentation.final RegExp
Recursively convert tilde (upto) expressions into negation and star.final RegExp
rev()
Creates a new regexp that matches the reverse text of this one.(package private) static String
Reverses a string.int
The approximate number of NFA states this expression will need (only works correctly after macro expansion and without negation)toString()
typeName()
String representation of the type of this regular expression.
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Field Details
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type
int typeThe type of the regular expression. This field will be filled with values from class sym.java (generated by cup)
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Constructor Details
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RegExp
public RegExp(int type) Create a new regular expression of the specified type.- Parameters:
type
- a value from the cup generated class sym.
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Method Details
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print
Returns a String-representation of this regular expression with the specified indentation.- Parameters:
tab
- a String that should contain only space characters and that is inserted in front of standard String-representation pf this object.- Returns:
- a
String
object.
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toString
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typeName
String representation of the type of this regular expression. -
isCharClass
public boolean isCharClass()Find out if this regexp is a char class or equivalent to one.- Returns:
- true if the regexp is equivalent to a char class.
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size
The approximate number of NFA states this expression will need (only works correctly after macro expansion and without negation)- Parameters:
macros
- macro table for expansion- Returns:
- a int.
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revString
Reverses a string. -
resolveTilde
Recursively convert tilde (upto) expressions into negation and star.- Returns:
- new RegExp equivalent to the current one, but without upto expressions.
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anyChar
Returns a regexp that matches any character:[^]
- Returns:
- the regexp for
[^]
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checkPrimClass
Confirms that the parameter is a RegExp1 of type sym.PRIMCLASS.- Parameters:
r
- the RegExp to check- Returns:
- r cast to RegExp1
- Throws:
CharClassException
- if r is not a RegExp1 or of type sym.PRIMCLASS.
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performClassOp
Performs the given set operation on the twoIntCharSet
parameters.- Parameters:
op
- the operation to perform (as @{link sym} constant)l
- the left operator of the expressionr
- the right operator of the expressionctxt
- the regular expression containing the provided operator- Returns:
- a new
IntCharSet
- Throws:
RegExpException
- forctxt
if the operator is not supported
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normalise
Normalise the regular expression to eliminate macro use (expand them), and compound character class expression (compute their content).- Returns:
- a regexp that contains only
IntCharSet
char classes and nosym.MACROUSE
.
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makeCCLs
Make character class partitions based on the classes mentioned in this regexp.Assumption: regexp is normalised.
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rev
Creates a new regexp that matches the reverse text of this one.- Returns:
- the reverse regexp
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