Tools.h++ Manual

5-4 104011 Tandem Computers Incorporated
5
which is an encapsulation of the Standard C library function strcoll() . This
function will return results computed according to the locale-specific collating
conventions set by category LC_COLLATE of the Standard C library function
setlocale() . Because this is a relatively expensive calculation, you may
want to pretransform one or more strings using the global function
RWCString strXForm(const RWCString&);
and then use compareTo() or one of the logical operators (==, !=, etc.) on the
results.
5.3 Substrings
A separate RWCSubString class supports substring extraction and
modification. There are no public constructors— RWCSubStrings are
constructed indirectly by various member functions of RWCString , and then
destroyed at the first opportunity. The resulting substring can be used in a
variety of situations.
For example, a substring can be created by an overloaded version of
operator()() This can then be used to initialize an RWCString :
RWCString s("this is a string");
// Construct an RWCString from a substring:
RWCString s2 = s(0, 4); // "this"
The result is a string s2 that contains a copy of the first four characters of s .
RWSubStrings may also be used as lvalues in an assignment, either to a
character string, or to an RWCString or RWCSubString:
// Construct an RWCString:
RWCString article("the");
RWCString s("this is a string");
s(0, 4) = "that"; // "that is a string"
s(8, 1) = article; // "that is the string"
Note – Assignment is not a conformal operation: the two sides of the
assignment operator need not have the same number of characters.