PRegularExpression Class Reference

A class representing a regular expression that may be used for locating patterns in strings. More...

#include <pstring.h>

Inheritance diagram for PRegularExpression:

List of all members.

Constructors & destructors
enum	{ Extended = 1, IgnoreCase = 2, AnchorNewLine = 4 }
	Flags for compiler options. More...
enum	{ NotBeginningOfLine = 1, NotEndofLine = 2 }
	Flags for execution options. More...
	PRegularExpression ()
	Create a new, empty, regular expression.
	PRegularExpression (const PString &pattern, int flags=IgnoreCase)
	Create and compile a new regular expression pattern.
	PRegularExpression (const char *cpattern, int flags=IgnoreCase)
	Create and compile a new regular expression pattern.
	PRegularExpression (const PRegularExpression &)
	Copy a regular expression.
PRegularExpression &	operator= (const PRegularExpression &)
	Assign a regular expression.
	~PRegularExpression ()
	Release storage for the compiled regular expression.
Status functions
enum	ErrorCodes {   NoError = 0, NoMatch, BadPattern, CollateError,   BadClassType, BadEscape, BadSubReg, UnmatchedBracket,   UnmatchedParen, UnmatchedBrace, BadBR, RangeError,   OutOfMemory, BadRepitition, PrematureEnd, TooBig,   UnmatchedRParen, NotCompiled }
	Error codes. More...
ErrorCodes	GetErrorCode () const
	Get the error code for the last Compile() or Execute() operation.
PString	GetErrorText () const
	Get the text description for the error of the last Compile() or Execute() operation.
const PString &	GetPattern () const
	Return the string which represents the pattern matched by the regular expression.
Public Member Functions
Overrides from class PObject
virtual void	PrintOn (ostream &strm) const
	Output the regular expression to the specified stream.
Compile & Execute functions
PBoolean	Compile (const PString &pattern, int flags=IgnoreCase)
	Compiler pattern.
PBoolean	Compile (const char *cpattern, int flags=IgnoreCase)
	Compiler pattern.
PBoolean	Execute (const PString &str, PINDEX &start, int flags=0) const
	Execute regular expression.
PBoolean	Execute (const PString &str, PINDEX &start, PINDEX &len, int flags=0) const
	Execute regular expression.
PBoolean	Execute (const char *cstr, PINDEX &start, int flags=0) const
	Execute regular expression.
PBoolean	Execute (const char *cstr, PINDEX &start, PINDEX &len, int flags=0) const
	Execute regular expression.
PBoolean	Execute (const PString &str, PIntArray &starts, int flags=0) const
	Execute regular expression.
PBoolean	Execute (const PString &str, PIntArray &starts, PIntArray &ends, int flags=0) const
	Execute regular expression.
PBoolean	Execute (const char *cstr, PIntArray &starts, int flags=0) const
	Execute regular expression.
PBoolean	Execute (const char *cstr, PIntArray &starts, PIntArray &ends, int flags=0) const
	Execute regular expression.
Static Public Member Functions
Miscellaneous functions
static PString	EscapeString (const PString &str)
	Escape all characters in the str parameter that have a special meaning within a regular expression.
Protected Attributes
PString	patternSaved
int	flagsSaved
void *	expression
ErrorCodes	lastError

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Detailed Description

A class representing a regular expression that may be used for locating patterns in strings.

The regular expression string is "compiled" into a form that is more efficient during the matching. This compiled form exists for the lifetime of the PRegularExpression instance.

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Member Enumeration Documentation

anonymous enum

Flags for compiler options.

Enumerator:

Extended	Use extended regular expressions.
IgnoreCase	Ignore case in search.
AnchorNewLine	If this bit is set, then anchors do not match at newline characters in the string. If not set, then anchors do match at newlines.

anonymous enum

Flags for execution options.

Enumerator:

NotBeginningOfLine	If this bit is set, then the beginning-of-line operator doesn't match the beginning of the string (presumably because it's not the beginning of a line). If not set, then the beginning-of-line operator does match the beginning of the string.
NotEndofLine	Like NotBeginningOfLine, except for the end-of-line.

enum PRegularExpression::ErrorCodes

Error codes.

Enumerator:

NoError	Success.
NoMatch	Didn't find a match (for regexec).
BadPattern	Invalid pattern.
CollateError	Not implemented.
BadClassType	Invalid character class name.
BadEscape	Trailing backslash.
BadSubReg	Invalid back reference.
UnmatchedBracket	Unmatched left bracket.
UnmatchedParen	Parenthesis imbalance.
UnmatchedBrace	Unmatched \.
BadBR	Invalid contents of \.
RangeError	Invalid range end.
OutOfMemory	Ran out of memory.
BadRepitition	No preceding re for repetition op.
PrematureEnd	Premature end.
TooBig	Compiled pattern bigger than 2^16 bytes.
UnmatchedRParen	Unmatched ) or \); not returned from regcomp.
NotCompiled	Miscellaneous error.

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Constructor & Destructor Documentation

PRegularExpression::PRegularExpression

(

)

Create a new, empty, regular expression.

PRegularExpression::PRegularExpression	(	const PString &	pattern,
		int	flags = IgnoreCase
	)

Create and compile a new regular expression pattern.

Parameters:

pattern	Pattern to compile
flags	Pattern match options

PRegularExpression::PRegularExpression	(	const char *	cpattern,
		int	flags = IgnoreCase
	)

Create and compile a new regular expression pattern.

Parameters:

cpattern	Pattern to compile
flags	Pattern match options

PRegularExpression::PRegularExpression

(

const PRegularExpression &

)

Copy a regular expression.

PRegularExpression::~PRegularExpression

(

)

Release storage for the compiled regular expression.

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Member Function Documentation

PBoolean PRegularExpression::Compile	(	const char *	cpattern,
		int	flags = IgnoreCase
	)

Compiler pattern.

The pattern is compiled into an internal format to speed subsequent execution of the pattern match algorithm.

Returns:

true if successfully compiled.

Parameters:

cpattern	Pattern to compile
flags	Pattern match options

PBoolean PRegularExpression::Compile	(	const PString &	pattern,
		int	flags = IgnoreCase
	)

Compiler pattern.

Parameters:

pattern	Pattern to compile
flags	Pattern match options

static PString PRegularExpression::EscapeString

(

const PString &

str

)

[static]

Escape all characters in the str parameter that have a special meaning within a regular expression.

Returns:

String with additional escape ('\') characters.

Parameters:

str	String to add esacpes to.

PBoolean PRegularExpression::Execute	(	const char *	cstr,
		PIntArray &	starts,
		PIntArray &	ends,
		int	flags = 0
	)			const

Execute regular expression.

Execute the pattern match algorithm using the previously compiled pattern.

The starts array is filled with as many matches as will fit into the array. If the the array size is zero then it is set to at least one for the first match found.

The ends array is set to the ending position of each substring whose start is returned in the starts array. This will always be set to the same size as that array.

Returns:

true if successfully compiled.

Parameters:

cstr	Source string to search
starts	List of match locations
ends	List of match ends
flags	Pattern match options

PBoolean PRegularExpression::Execute	(	const char *	cstr,
		PIntArray &	starts,
		int	flags = 0
	)			const

Execute regular expression.

Parameters:

cstr	Source string to search
starts	List of match locations
flags	Pattern match options

PBoolean PRegularExpression::Execute	(	const PString &	str,
		PIntArray &	starts,
		PIntArray &	ends,
		int	flags = 0
	)			const

Execute regular expression.

Parameters:

str	Source string to search
starts	List of match locations
ends	List of match ends
flags	Pattern match options

PBoolean PRegularExpression::Execute	(	const PString &	str,
		PIntArray &	starts,
		int	flags = 0
	)			const

Execute regular expression.

Parameters:

str	Source string to search
starts	List of match locations
flags	Pattern match options

PBoolean PRegularExpression::Execute	(	const char *	cstr,
		PINDEX &	start,
		PINDEX &	len,
		int	flags = 0
	)			const

Execute regular expression.

Parameters:

cstr	Source string to search
start	First match locations
len	Length of match
flags	Pattern match options

PBoolean PRegularExpression::Execute	(	const char *	cstr,
		PINDEX &	start,
		int	flags = 0
	)			const

Execute regular expression.

Parameters:

cstr	Source string to search
start	First match locations
flags	Pattern match options

PBoolean PRegularExpression::Execute	(	const PString &	str,
		PINDEX &	start,
		PINDEX &	len,
		int	flags = 0
	)			const

Execute regular expression.

Parameters:

str	Source string to search
start	First match locations
len	Length of match
flags	Pattern match options

PBoolean PRegularExpression::Execute	(	const PString &	str,
		PINDEX &	start,
		int	flags = 0
	)			const

Execute regular expression.

Parameters:

str	Source string to search
start	First match locations
flags	Pattern match options

ErrorCodes PRegularExpression::GetErrorCode

(

)

const

Get the error code for the last Compile() or Execute() operation.

Returns:

Error code.

PString PRegularExpression::GetErrorText

(

)

const

Get the text description for the error of the last Compile() or Execute() operation.

Returns:

Error text string.

const PString& PRegularExpression::GetPattern

(

)

const [inline]

Return the string which represents the pattern matched by the regular expression.

PRegularExpression& PRegularExpression::operator=

(

const PRegularExpression &

)

Assign a regular expression.

virtual void PRegularExpression::PrintOn

(

ostream &

strm

)

const [virtual]

Output the regular expression to the specified stream.

Parameters:

strm	I/O stream to output to.

Reimplemented from PObject.

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Member Data Documentation

void* PRegularExpression::expression [protected]

int PRegularExpression::flagsSaved [protected]

ErrorCodes PRegularExpression::lastError [mutable, protected]

PString PRegularExpression::patternSaved [protected]

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The documentation for this class was generated from the following file:

• pstring.h

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