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ost::StringTokenizer(3) Library Functions Manual ost::StringTokenizer(3)

NAME

ost::StringTokenizer - Splits delimited string into tokens.

SYNOPSIS

#include <tokenizer.h>

Classes


class iterator
The input forward iterator for tokens. class NoSuchElementException
Exception thrown, if someone tried to read beyond the end of the tokens.

Public Member Functions


StringTokenizer (const char *str, const char *delim, bool skipAllDelim=false, bool trim=false)
creates a new StringTokenizer for a string and a given set of delimiters. StringTokenizer (const char *s)
create a new StringTokenizer which splits the input string at whitespaces. iterator begin () const
returns the begin iterator void setDelimiters (const char *d)
changes the set of delimiters used in subsequent iterations. iterator begin (const char *d)
returns a begin iterator with an alternate set of delimiters. const iterator & end () const
the iterator marking the end.

Static Public Attributes


static const char *const SPACE
a delimiter string containing all usual whitespace delimiters.

Friends


class StringTokenizer::iterator

Detailed Description

Splits delimited string into tokens.

The StringTokenizer takes a pointer to a string and a pointer to a string containing a number of possible delimiters. The StringTokenizer provides an input forward iterator which allows to iterate through all tokens. An iterator behaves like a logical pointer to the tokens, i.e. to shift to the next token, you've to increment the iterator, you get the token by dereferencing the iterator.

Memory consumption: This class operates on the original string and only allocates memory for the individual tokens actually requested, so this class allocates at maximum the space required for the longest token in the given string. Since for each iteration, memory is reclaimed for the last token, you MAY NOT store pointers to them; if you need them afterwards, copy them. You may not modify the original string while you operate on it with the StringTokenizer; the behaviour is undefined in that case.

The iterator has one special method 'nextDelimiter()' which returns a character containing the next delimiter following this tokenization process or '\0', if there are no following delimiters. In case of skipAllDelim, it returns the FIRST delimiter.

With the method 'setDelimiters(const char*)' you may change the set of delimiters. It affects all running iterators.

Example:


StringTokenizer st('mary had a little lamb;its fleece was..', ' ;');
StringTokenizer::iterator i;
for (i = st.begin() ; i != st.end() ; ++i) {
cout << 'Token: '' << *i << ''\t';
cout << ' next Delim: '' << i.nextDelimiter() << ''' << endl;
}

Author

Henner Zeller H.Zeller@acm.org

License:\n LGPL

Constructor & Destructor Documentation

ost::StringTokenizer::StringTokenizer (const char * str, const char * delim, bool skipAllDelim = false, bool trim = false)

creates a new StringTokenizer for a string and a given set of delimiters.

Parameters

str String to be split up. This string will not be modified by this StringTokenizer, but you may as well not modfiy this string while tokenizing is in process, which may lead to undefined behaviour.
delim String containing the characters which should be regarded as delimiters.
skipAllDelim OPTIONAL. true, if subsequent delimiters should be skipped at once or false, if empty tokens should be returned for two delimiters with no other text inbetween. The first behaviour may be desirable for whitespace skipping, the second for input with delimited entry e.g. /etc/passwd like files or CSV input. NOTE, that 'true' here resembles the ANSI-C strtok(char *s,char *d) behaviour. DEFAULT = false
trim OPTIONAL. true, if the tokens returned should be trimmed, so that they don't have any whitespaces at the beginning or end. Whitespaces are any of the characters defined in StringTokenizer::SPACE. If delim itself is StringTokenizer::SPACE, this will result in a behaviour with skipAllDelim = true. DEFAULT = false

ost::StringTokenizer::StringTokenizer (const char * s)

create a new StringTokenizer which splits the input string at whitespaces. The tokens are stripped from whitespaces. This means, if you change the set of delimiters in either the 'begin(const char *delim)' method or in 'setDelimiters()', you then get whitespace trimmed tokens, delimited by the new set. Behaves like StringTokenizer(s, StringTokenizer::SPACE,false,true);

Member Function Documentation

iterator ost::StringTokenizer::begin () const [inline]

returns the begin iterator

iterator ost::StringTokenizer::begin (const char * d) [inline]

returns a begin iterator with an alternate set of delimiters.

const iterator& ost::StringTokenizer::end (void) const [inline]

the iterator marking the end.

void ost::StringTokenizer::setDelimiters (const char * d) [inline]

changes the set of delimiters used in subsequent iterations.

Friends And Related Function Documentation

friend class StringTokenizer::iterator [friend]

Member Data Documentation

const char* const ost::StringTokenizer::SPACE [static]

a delimiter string containing all usual whitespace delimiters. These are space, tab, newline, carriage return, formfeed and vertical tab. (see isspace() manpage).

Author

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Sun Dec 27 2020 GNU CommonC++