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Floating-Point Precision

boost::cnv::strtol cnv;

BOOST_TEST(  "12.3" == convert<string>(12.3456, cnv(arg::precision = 1)).value());
BOOST_TEST( "12.35" == convert<string>(12.3456, cnv(arg::precision = 2)).value());
BOOST_TEST("12.346" == convert<string>(12.3456, cnv(arg::precision = 3)).value());

BOOST_TEST(  "-12.3" == convert<string>(-12.3456, cnv(arg::precision = 1)).value());
BOOST_TEST( "-12.35" == convert<string>(-12.3456, cnv(arg::precision = 2)).value());
BOOST_TEST("-12.346" == convert<string>(-12.3456, cnv(arg::precision = 3)).value());