我对warnings
附注不抱怨“NaN”和“nan”是非数字的事实感到有点惊讶(也很害怕)。为什么根据警告编译指示'NaN'数字?
为什么warnings
对他们没有排出习惯'Argument isn't numeric in addition (+)
?
测试用例
$ perl -Mstrict -wE 'say 0+$_ for qw/string NaN nan fail/;'
Argument "string" isn't numeric in addition (+) at -e line 1.
0
0
0
Argument "fail" isn't numeric in addition (+) at -e line 1.
0
http://en.wikipedia.org/wiki/NaN'NaN'是一个浮点数的有效值,就像+/-无穷大一样。 – biziclop 2012-07-05 13:58:55