So you could have predicted this yesterday? Just because it's codified somewhere, it doesn't make it clear, or anything other than a whim, or a product of circumstances, at best. That's not how languages should be defined, even if PHP clearly demonstrates that they can end up that way by chance.
Rasmus' lack of foresight does not make it reasonable.
Earlier versions have said the comparison converts the numbers to integers though, which may be incorrect, and misleading if it was. Did PHP not convert float-like strings to floats in, eg, 2009? http://web.archive.org/web/20091024233139/http://www.php.net...
The point, however, is that you shouldn't pepper your language with operations which have consequences as hard to foresee as this with no good reason, and I really don't think that saving yourself some type conversions here and there would do.
"no good reason" is entirely subjective, though. If your purpose is to make the language simpler to newcomers, implicit conversions everywhere are a great way to get things done. And the popularity of PHP (especially for new-to-programming people) heavily supports that they made the correct decision to work well for that market.
The same kind of logic is used to make `false == ""` true. Or any 'falsy' language. If you want strictly typed behavior, yes, it's stupid to do that. If you don't, then it makes some things simpler, at the expense of more edge cases that are unlikely to happen - note that this bug was reported in 2011, and people are acting like it's a new thing. Because it comes up so rarely that, while it technically exists, many people never encounter it.
> "no good reason" is entirely subjective, though. If your purpose is to make the language simpler to newcomers, implicit conversions everywhere are a great way to get things done. And the popularity of PHP (especially for new-to-programming people) heavily supports that they made the correct decision to work well for that market.
You are right, in a way. Sure, it may attract and retain more newcomers, but that's like saying that tobacco is "teenager friendly". I think it's not beginner friendly at all if you must have years of experience to avoid the innumerable pitfalls which PHP lays for you all over the place, learning, e.g. the range of Integers in PHP, which defines when a string will be either a float or an int, or that you should actually use strcmp.
In Python, Ruby, or heck, Haskell, you'd just have to do == and there would be no surprises.
I agree entirely, but we're thinking like programmers. Grab someone who's never programmed at all and ask them if `123 is equal to "123"`.
This essentially breaks down to the top-down vs bottom-up education style debate. You can learn the gritty details and get caught up in minor details that may not matter in other languages, or learn how to do something, and get tripped up by the details in other languages. Similarly, we could teach kids abstract algebra, or basic +-*/ and then over-simplify when they try to divide by zero.
Neither is ideal, both have useful traits and problems, so we have to pick one. Or try to come up with something radically different.
edit: to ask it another way: if PHP is a massively-popular gateway drug to the world of programming, but it gives some people horrible flashbacks for the rest of their lives, do you want to make it illegal and close the door to a huge number of people?
Oh, and "everyone knows that PHP lights the upper-rightmost pixel in you screen purple and will crash if there's no screen" would not, in fact, justify such a thing.
Alright, I'll spell it out for you: the behaviour may be what you'd expect from floating-point comparisons, but it doesn't have to be a floating point comparison in the first place.
No, it doesn't. Language designers make lots of decisions that end up being silly. But they make them. In PHP, if it looks like a number, it will get treated like a number when being compared via ==. It's a simple, well-established, fundamental rule.
Sadly, while '===' is the quick fix, you then have to litter your code with type casting operators if you're comparing numbers, particularly those sourced from, say, a database, where everything is returned as a string. Or from GET or POST data, where everything is a string.
This tripped me up when I was trying to compare two numbers, one of which was the result of a COUNT query via PDO. Of course, that COUNT result was a string.
I suppose if you worked entirely with strings it's alright. Or it wouldn't be so bad if you could make the reasonable assumption that functions returned appropriately typed data.
Your lack of knowledge does not make it obscure.