TRegexp Class Reference

Regular expression class.

'^'             // start-of-line anchor
'$'             // end-of-line anchor
'.'             // matches any character
'['             // start a character class
']'             // end a character class
'^'             // negates character class if 1st character
'*'             // Kleene closure (matches 0 or more)
'+'             // Positive closure (1 or more)
'?'             // Optional closure (0 or 1)

Note that the '|' operator (union) is not supported, nor are parentheses (grouping). Therefore "a|b" does not match "a".

Standard classes like [:alnum:], [:alpha:], etc. are not supported, only [a-zA-Z], [^ntf] and so on.

Warning: The preferred way to use regular expressions is via std::regex. E.g., Index() functions may return incorrect result.

Definition at line 31 of file TRegexp.h.

Public Types
enum	EStatVal { kOK = 0 , kIllegal , kNomem , kToolong }

Public Member Functions
	TRegexp (const char *re, Bool_t wildcard=kFALSE)
	Create a regular expression from the input string.
	TRegexp (const TRegexp &re)
	Copy ctor.
	TRegexp (const TString &re)
	Create a regular expression from a TString.
virtual	~TRegexp ()
	Destructor.
Ssiz_t	Index (const TString &str, Ssiz_t *len, Ssiz_t start=0) const
	Find the first occurrence of the regexp in string and return the position, or -1 if there is no match.
virtual TClass *	IsA () const
TRegexp &	operator= (const char *re)
	Assignment operator taking a char* and assigning it to a regexp.
TRegexp &	operator= (const TRegexp &re)
	Assignment operator.
TRegexp &	operator= (const TString &re)
	Assignment operator taking a TString.
EStatVal	Status ()
	Check status of regexp.
virtual void	Streamer (TBuffer &)
void	StreamerNVirtual (TBuffer &ClassDef_StreamerNVirtual_b)

Static Public Member Functions
static TClass *	Class ()
static const char *	Class_Name ()
static constexpr Version_t	Class_Version ()
static const char *	DeclFileName ()

Private Member Functions
void	CopyPattern (const TRegexp &re)
	Copy the regular expression pattern.
void	GenPattern (const char *re)
	Generate the regular expression pattern.
const char *	MakeWildcard (const char *re)
	This routine transforms a wildcarding regular expression into a general regular expression used for pattern matching.

Private Attributes
Pattern_t *	fPattern
EStatVal	fStat

Static Private Attributes
static const unsigned	fgMaxpat = 2048

#include <TRegexp.h>

Member Enumeration Documentation

EStatVal

enum TRegexp::EStatVal

Enumerator
kOK
kIllegal
kNomem
kToolong

Definition at line 34 of file TRegexp.h.

Constructor & Destructor Documentation

TRegexp() [1/3]

TRegexp::TRegexp	(	const char *	re,
		Bool_t	wildcard = kFALSE
	)

Create a regular expression from the input string.

If wildcard is true then the input string will first be interpreted as a wildcard expression by MakeWildcard(), and the result then interpreted as a regular expression.

Definition at line 54 of file TRegexp.cxx.

TRegexp() [2/3]

TRegexp::TRegexp

(

const TString &

re

)

Create a regular expression from a TString.

Definition at line 65 of file TRegexp.cxx.

TRegexp() [3/3]

TRegexp::TRegexp

(

const TRegexp &

re

)

Copy ctor.

Definition at line 73 of file TRegexp.cxx.

~TRegexp()

TRegexp::~TRegexp ( )

virtual

Destructor.

Definition at line 81 of file TRegexp.cxx.

Member Function Documentation

Class()

static TClass * TRegexp::Class ( )

static

Returns

TClass describing this class

Class_Name()

static const char * TRegexp::Class_Name ( )

static

Returns

Name of this class

Class_Version()

static constexpr Version_t TRegexp::Class_Version ( )

inlinestaticconstexpr

Returns

Version of this class

Definition at line 57 of file TRegexp.h.

CopyPattern()

void TRegexp::CopyPattern ( const TRegexp &  re )

private

Copy the regular expression pattern.

Definition at line 131 of file TRegexp.cxx.

DeclFileName()

static const char * TRegexp::DeclFileName ( )

inlinestatic

Returns

Name of the file containing the class declaration

Definition at line 57 of file TRegexp.h.

GenPattern()

void TRegexp::GenPattern ( const char *  re )

private

Generate the regular expression pattern.

Definition at line 121 of file TRegexp.cxx.

Index()

Ssiz_t TRegexp::Index	(	const TString &	string,
		Ssiz_t *	len,
		Ssiz_t	i = 0
	)		const

Find the first occurrence of the regexp in string and return the position, or -1 if there is no match.

Len is length of the matched string and i is the offset at which the matching should start. Please, see the Warning in the class documentation above.

Definition at line 213 of file TRegexp.cxx.

IsA()

virtual TClass * TRegexp::IsA ( ) const

inlinevirtual

Returns

TClass describing current object

Definition at line 57 of file TRegexp.h.

MakeWildcard()

const char * TRegexp::MakeWildcard ( const char *  re )

private

This routine transforms a wildcarding regular expression into a general regular expression used for pattern matching.

When using wildcards the regular expression is assumed to be preceded by a "^" (BOL) and terminated by a "$" (EOL). Also, all "*"'s and "?"'s (closures) are assumed to be preceded by a "." (i.e. any character, except "/"'s) and all .'s are escaped (so *.ps is different from *.eps). The special treatment of "/" allows the easy matching of pathnames, e.g. "*.root" will match "aap.root", but not "pipo/aap.root".

Definition at line 148 of file TRegexp.cxx.

operator=() [1/3]

TRegexp & TRegexp::operator=

(

const char *

re

)

Assignment operator taking a char* and assigning it to a regexp.

Definition at line 101 of file TRegexp.cxx.

operator=() [2/3]

TRegexp & TRegexp::operator=

(

const TRegexp &

re

)

Assignment operator.

Definition at line 89 of file TRegexp.cxx.

operator=() [3/3]

TRegexp & TRegexp::operator=

(

const TString &

re

)

Assignment operator taking a TString.

Definition at line 111 of file TRegexp.cxx.

Status()

TRegexp::EStatVal TRegexp::Status

(

)

Check status of regexp.

Definition at line 235 of file TRegexp.cxx.

Streamer()

virtual void TRegexp::Streamer ( TBuffer &  )

virtual

StreamerNVirtual()

void TRegexp::StreamerNVirtual ( TBuffer &  ClassDef_StreamerNVirtual_b )

inline

Definition at line 57 of file TRegexp.h.

Member Data Documentation

fgMaxpat

const unsigned TRegexp::fgMaxpat = 2048

staticprivate

Definition at line 39 of file TRegexp.h.

fPattern

Pattern_t* TRegexp::fPattern

private

Definition at line 37 of file TRegexp.h.

fStat

EStatVal TRegexp::fStat

private

Definition at line 38 of file TRegexp.h.