RWWSubString(3C++) RWWSubString(3C++)
NameRWWSubString - Rogue Wave library class
Synopsis
#include <rw/wstring.h>
RWWString s(L"test string");
s(6,3); // "tri"
Description
The class RWWSubString allows some subsection of an RWWString to be
addressed by defining a starting position and an extent. For example the
7th through the 11th elements, inclusive, would have a starting position
of 7 and an extent of 5. The specification of a starting position and
extent can also be done in your behalf by such functions as
RWWString::strip() or the overloaded function call operator taking a
regular expression as an argument. There are no public constructors --
RWWSubStrings are constructed by various functions of the RWWString class
and then destroyed immediately. A zero lengthsubstring is one with a
defined starting position and an extent of zero. It can be thought of as
starting just before the indicated character, but not including it. It
can be used as an lvalue. A null substring is also legal and is
frequently used to indicate that a requested substring, perhaps through a
search, does not exist. A null substring can be detected with member
function isNull(). However, it cannot be used as an lvalue.
Persistence
None
Example
#include <rw/rstream.h>
#include <rw/wstring.h>
main(){
RWWString s(L"What I tell you is true.");
// Create a substring and use it as an lvalue:
s(15,0) = RWWString(L" three times");
cout << s << endl;
return 0;
}
Program output:
What I tell you three times is true.
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RWWSubString(3C++) RWWSubString(3C++)
Assignment Operators
void
operator=(const RWWString&);
Assignment from an RWWString. The statements:
RWWString a;
RWWString b;
b(2, 3) = a;
will copy a's data into the substring b(2,3). The number of elements
need not match: if they differ, b will be resized appropriately. If self
is the null substring, then the statement has no effect.
void
operator=(const wchar_t*);
Assignment from a wide character string. Example:
RWWString wstr(L"Mary had a little lamb");
wchar_t dat[] = L"Perrier";
wstr(11,4) = dat; // "Mary had a Perrier"
Note that the number of characters selected need not match: if they
differ, wstr will be resized appropriately. If self is the null
substring, then the statement has no effect.
Indexing Operators
wchar_t
operator[](size_t i);
wchar_t&
operator[](size_t i) const;
Returns the ith character of the substring. The first variant can be
used as an lvalue, the second cannot. The index i must be between zero
and the length of the substring less one. Bounds checking is performed:
if the index is out of range, then an exception of type RWBoundsErr will
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RWWSubString(3C++) RWWSubString(3C++)
be thrown.
wchar_t
operator()(size_t i);
wchar_t&
operator()(size_t i) const;
Returns the ith character of the substring. The first variant can be
used as an lvalue, the second cannot. The index i must be between zero
and the length of the substring less one. Bounds checking is enabled by
defining the pre-processor macro RWBOUNDS_CHECK before including
<rw/wstring.h>. In that case, if the index is out of range, then an
exception of type RWBoundsErr will be thrown.
Public Member Functions
RWBoolean
isNull() const;
Returns TRUE if this is a null substring.
size_t
length() const;
Returns the extent (length) of the RWWSubString.
RWBoolean
operator!() const;
Returns TRUE if this is a null substring.
size_t
start() const;
Returns the starting element of the RWWSubString.
void
toLower();
Changes all upper-case letters in self to lower-case. Uses the C library
function towlower().
void
toUpper();
Changes all lower-case letters in self to upper-case. Uses the C library
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RWWSubString(3C++) RWWSubString(3C++)
function towupper().
Global Logical Operators
RWBoolean
operator==(const RWWSubString&, const RWWSubString&);
RWBoolean
operator==(const RWWString&, const RWWSubString&);
RWBoolean
operator==(const RWWSubString&, const RWWString& );
RWBoolean
operator==(const wchar_t*, const RWWSubString&);
RWBoolean
operator==(const RWWSubString&, const wchar_t* );
Returns TRUE if the substring is lexicographically equal to the wide
character string or RWWString argument. Case sensitivity is exact.
RWBoolean
operator!=(const RWWString&, const RWWString& );
RWBoolean
operator!=(const RWWString&, const RWWSubString&);
RWBoolean
operator!=(const RWWSubString&, const RWWString& );
RWBoolean
operator!=(const wchar_t*, const RWWString& );
RWBoolean
operator!=(const RWWString&, const wchar_t* );
Returns the negation of the respective operator==()
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