4 ms·
in javascript: 1 == '01' --> true 0 == 'x' --> false 1 == '1' --> true true == 'asdf' --> false '-2' == 2 --> true '-2' == 0 --> false Seems like in java
by catch23 17y ago
in javascript:
1 == '01' --> true
0 == 'x' --> false
1 == '1' --> true
true == 'asdf' --> false
'-2' == 2 --> true
'-2' == 0 --> false
Seems like in javascript, the coercing is much more sane. In php, all of the above statements would end up true.
- encoderer 17y agoI don't have a PHP runtime in front of me, but IIRC the first one on your list and the last 2 will evaluate false in php
- ars 17y agoJavascript is not totally sane: '\t\r\n' == 0 --> true And not transitive: "false" == "0" --> false "0" == 0 --> true 0 == false --> true false == "false" --> false It's basically impossible to make a loosely typed equality perfect. PHP is much more strict about the rules used when doing the comparison, javascript is more loose. It tries to guess. When comparing a string to a number, if the string looks like a number it's converted to one. But if it doesn't, then instead the number get converted to a string. This works well most of the time - but not always, since it can surprise you. PHP is more strict, so it doesn't work as often, but it fails more consistently, so it's easier to find the problem. Another example: "1" == "01" --> false "01" == 1 --> true 1 == "1" --> true
- BerislavLopac 17y agoThe funny thing is that in Javascript: 12 == parseInt('012') returns false. :)
- mhansen 17y agoA leading zero usually means 'this number is octal', so parseInt returns 10. Not very intuitive notation, however.