From:
http://web.archive.org/web/20090221144611/http://faqts.com/knowledge_base/view.phtml/aid/1/fid/40
Speed. There is a difference between the two, but speed-wise it
should be irrelevant which one you use. echo is marginally faster
since it doesn't set a return value if you really want to get down to the
nitty gritty.
Expression. print()
behaves like a function in that you can do:
$ret = print "Hello World"
; And $ret
will be 1
. That means that print
can be used as part of a more complex expression where echo cannot. An
example from the PHP Manual:
$b ? print "true" : print "false";
print is also part of the precedence table which it needs to be if it
is to be used within a complex expression. It is just about at the bottom
of the precedence list though. Only ,
AND
OR
XOR
are lower.
- Parameter(s). The grammar is:
echo expression [, expression[,
expression] ... ]
But echo ( expression, expression )
is not valid.
This would be valid: echo ("howdy"),("partner")
; the same as: echo
"howdy","partner"
; (Putting the brackets in that simple example
serves
no purpose since there is no operator precedence issue with a single
term like that.)
So, echo without parentheses can take multiple parameters, which get
concatenated:
echo "and a ", 1, 2, 3; // comma-separated without parentheses
echo ("and a 123"); // just one parameter with parentheses
print()
can only take one parameter:
print ("and a 123");
print "and a 123";
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