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FBB::X2a(3bobcat) X-to-ASCII conversions FBB::X2a(3bobcat)


FBB::X2a - Objects performing x-to-Ascii conversions


#include <bobcat/x2a>
Linking option: -lbobcat


FBB:X2a objects convert values of any (insertable) type to text. The returned text is automatically made available as a standard C++ string.


All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the namespace FBB.




X2a(T const &value):
In this constructor T may be any type that can be inserted into an o[string]stream.
X2a(double value, size_t behind):
Double value is truncated to behind digits behind the decimal dot. If a value doesn’t occupy behind digits behind the decimal point, then missing digits are added as 0. For example, a value of 7.1, will be displayed as 7.10 if two digits behind the decimal dot are requested. A value of 7 will be displayed as 7.00.
X2a(double value, size_t width, size_t behind, std::ios::fmtflags flags = std::ios::right):
The value is displayed over width character positions, extending the amount if the value so requires. The converted value is placed right-aligned into the field of width characters.

The copy constructor and the copy assignment operator are available.


bool lastFail():
This member returns true if the last conversion failed (i.e., the object’s fail() member returned true and returns false otherwise). This member allows checks on the success of the extraction/conversion using anonymous A2x objects. The member also returns true when no conversions have as yet been performed.
Note that this member is a thread-unsafe static member: in a multithreaded program locks may be required to ensure that the proper conversion result is inspected.


All members of std::ostringstream are available, as FBB::X2a inherits from this class. In particular ostringstream::str() can be used to obtain the content of an X2a object’s text buffer.


operator std::ostream &operator<<(std::ostream &ostr, X2a const &x2a):
This conversion operator inserts the textual representation of the x2a parameter value into the provided ostream.
operator std::string const() const:
this conversion operator returns the information stored inside the FBB::X2a object.


string is(X2a(5)); // initializes `is’ with "5"
string ds(X2a(5.25)); // initializes `ds’ with "5.25"
cout << X2a(7.0 / 3, 4) << endl;
// display a value using 4 digits behind the
// decimal dot.
cout << X2a(7.0 / 3, 8, 4) << endl;
// display a value over 8 positions, right
// adjusted, 4 digits behind the decimal dot.
cout << X2a(7.0 / 3, 8, 4, std::ios::left) << endl;
// display a value over 8 positions, left
// adjusted, 4 digits behind the decimal dot.


bobcat/x2a - defines the class interface


bobcat(7), a2x(3bobcat)


The functionality of this class is to a large extent also offered by the C++ function std::to_string.

BOBCAT PROJECT FILES gitlab project page;
bobcat_5.07.00-x.dsc: detached signature;
bobcat_5.07.00-x.tar.gz: source archive;
bobcat_5.07.00-x_i386.changes: change log;
libbobcat1_5.07.00-x_*.deb: debian package containing the libraries;
libbobcat1-dev_5.07.00-x_*.deb: debian package containing the libraries, headers and manual pages;


Bobcat is an acronym of `Brokken’s Own Base Classes And Templates’.


This is free software, distributed under the terms of the GNU General Public License (GPL).


Frank B. Brokken (

2005-2020 libbobcat-dev_5.07.00