This blog post has explored this question to a greater depth than you may have even known was possible.
Jesse Dhillon
2010-08-22 18:30:16
+3
A:
Extraordinary stupid article.
Col. Shrapnel
2010-08-22 19:09:08
@Col Must've had his feelings hurt because of getting the "interview question for the PHP developer who thinks they’re hot shit" wrong. One of the most arrogant and clueless posters on PHP on this site.
pessimopoppotamus
2010-08-22 19:21:48
+1
A:
Two differences:
print has a return value, echo doesn't. Therefore print is slightly slower but may be used in function context.
echo accepts multiple arguments. So you may write echo $a, $b instead of echo $a . $b. The former one will be faster, because the strings are echoed directly, without the necessity of first copying them to a new chunk of memory.
Concerning the parentheses: They are simply wrong in my eyes. They have no function at all. You could as well write echo (((((((((($a)))))))))); it is simply stupidity and/or ignorance. Furthermore it increases the chance of misinterpretation. For example print("foo") && print("bar") does not print foobar, because PHP interprets this as print(("foo") && print("bar")). So bar1 would be printed, even though it looks different.
nikic
2010-08-22 18:36:31
I know Python is not PHP, but they [banned](http://docs.python.org/release/3.0.1/whatsnew/3.0.html#print-is-a-function) the use of `print 'something'`, now you always have to use `print('something')` with the parentheses.
pessimopoppotamus
2010-08-22 18:44:19
No. It does make a difference. Even though it outputs the same the version with parentheses *looks* different. The parentheses and function like formatting make it look different. At least I would be fooled into thinking that it outputs `foobar`, if I didn't stop to think about it.
nikic
2010-08-22 19:00:45
Yes, you are right, it outputs the same thing. Maybe I didn't explain my point clearly. I'm talking about the understandability of the code, not of the functionality. The functionality doesn't change, that's correct.
nikic
2010-08-22 19:03:40
Though there actually is one case, there using parentheses will not only make the code less understandable, but will actually break things. If you have a function which returns by reference `return($a)` will not work, because it will not return a reference to `$a`, but the result of the expression `($a)`, which obviously is a value, not a reference. But this is off topic, because we're talking about print and echo ^^
nikic
2010-08-22 19:09:30
Simply see the third note on http://php.net/return. It is explained there.
nikic
2010-08-22 19:29:26
Downvoting this because of a) you are wrong b) extraordinarily stupid comment on a great article
pessimopoppotamus
2010-08-22 19:17:40
He's got a point that the article isn't of great importance to any reasonable developer (premature optimization is the root of all evil, we know that ^^). But this answer is simply wrong, -1.
nikic
2010-08-22 19:20:57
@nik Those who don't know, and most importantly **don't care** about the code underneath are doomed to write shitty programs
pessimopoppotamus
2010-08-22 19:23:27
@pessimopoppotamus well you are who don't really know but only read some stupid articles. I don't blame you because there are a lot of your kind around. I've already got accustomed with ignorant downvotes. It's hard to find a thinking person on SO
Col. Shrapnel
2010-08-22 19:31:43
@Col if you are going to serial downvote me, leave a comment with the reason. No need to be a coward.
pessimopoppotamus
2010-08-22 19:34:32
@pes That's the problem with PHP, it's so easy a monkey write programs with it. Then we got all these high school kids who think they are hot shit, when they are *just* shit.
quantumSoup
2010-08-22 19:36:35
@pess Why not? I'm already a devil in your eyes lol. will it make a difference? :)
Col. Shrapnel
2010-08-22 19:36:55
@nikic in the *real life* there is no difference. But for one who want to feel self-important - there, sure, is.
Col. Shrapnel
2010-08-22 19:39:49
@Col Nice thinking. I see a bright career at McDonald's for you.
NullUserException
2010-08-22 19:42:19
Col, your answer is wrong, the downvotes are perfectly legitimate. Even though you would maybe be right saying that there is no *significant* difference - most is coding standards and preference - saying that it is wrong is simply wrong.
nikic
2010-08-22 19:43:01
Col. Shrapnel
2010-08-22 19:46:14
@Jesse You are just wrong. I am one of the little few here who ever curious. And open your eyes, there are thousands ones here, who is asking you to actually optimize your apps with this information.
Col. Shrapnel
2010-08-23 04:00:24
Please, could we stop this discussion? And Col, if you haven't noticed, I thing you've got a point (and I think I said that, didn't I?) But your formulation is wrong and it is definitely wrong; I really don't know what you're disagreeing about. If you had written `There is no big difference` I would be okay with it. But your current answer is wrong!
nikic
2010-08-23 11:23:14