The use of "{" and "}"

[rtcary]

In this expression

$img = imagecreatefromjpeg( "{$pathToImages}{$fname}" );

are the "{" and "}" in place of using a "." to concatenate the strings?

Thank you...

Todd

[laserlight]

I suggest that you read the PHP manual on strings, especially the section on variable parsing.

[rtcary]

Thanks! Been a while since I read about strings!

[Lord_Yggdrasill]

Well there is no significant difference between using concatenation operators and curly brackets to join strings. I personally prefer using curly brackets, since the code is easy to read this way. Some may prefer concatenation operators, it is about religion(and in fact I really cant understand why some professional coders claim its 'wrong' to use curly brackets). I'd recommend you to be consistent though, so pick a style and stick to it.

[rtcary]

Well stated! Thank you.

Todd

[NogDog]

Well, the braces are totally optional in this particular case. Any of these will work, and at least in this particular circumstance I'd opt for the last one, as it's easiest to type and, totally in my opinion, the easiest to read:

<?php
$foo = 'Foo';
$bar = 'Bar';
echo "{$foo}{$bar}";
echo PHP_EOL;
echo "$foo$bar";
echo PHP_EOL;
echo $foo.$bar;

[Lord_Yggdrasill]

NogDog;11013273 wrote:

Well, the braces are totally optional in this particular case. Any of these will work, and at least in this particular circumstance I'd opt for the last one, as it's easiest to type and, totally in my opinion, the easiest to read:

<?php
$foo = 'Foo';
$bar = 'Bar';
echo "{$foo}{$bar}";
echo PHP_EOL;
echo "$foo$bar";
echo PHP_EOL;
echo $foo.$bar;

Well of course it is not hard to read something like $foo.$bar, but something like $foo."bar" can be a problem if used a lot in one long string concatenation. Let's say something like this can be a pain in the butt:

$sentence1."Sentence 2 is here. Sentence 3 coming along.".$sentence4."Now we have sentence 5.";

Yeah, it confuses me if the sentence is long enough and has dot in a substring itself. Its kinda hard to read with concatenation with so many dots going on with double/single quote in between, Id prefer writing it in curly brackets:

"{$sentence1}Sentence 2 is here. Sentence 3 coming along{$sentence4}Now we have sentence 5.";

Is it easier to read now? Well for me it is, people are different though so I cant say the same for those who prefer using concatenation all the time. It's a matter of religion after all.

[NogDog]

Yes, there are times to use complex notation (curly braces), times when maybe printf() might be better, etc., but in the OP's original post, there was no syntactic need for the complex notation, so in that particular case it was either purely a stylistic choice (which does not make it invalid, just a matter of choice and style) or it was based on a misconception that there was some syntactic/functional reason to use it in that situation.

$string = sprintf(
  "%sSentence 2 is here. Sentence 3 coming along%sNow we have sentence 5.",
  htmlentities($sentence1, ENT_QUOTES),
  htmlentities($lang4, ENT_QUOTES)
);

🙂

[Derokorian]

I tend to prefer concatenation, though I sometimes use sprintf instead depending on the situation, as then I can do whatever I want and not change notation (function call, object properties, primitive variables) the one thing I do different ygg is I use spacing around the dots and vars to make it more obvious:

echo 'This is a ' . $string . '. My favorite color is ' . $color[2] . '. My username is ' . $user->name . '. Also, ' . htmlentities($user->description);

[traq]

Lord Yggdrasill;11013277 wrote:

Is it easier to read now? Well for me it is, people are different though so I cant say the same for those who prefer using concatenation all the time. It's a matter of religion after all.

...? this is not directly an issue with concatenation, and curly brackets are not an alternate concatenation operator.
it's certainly not a matter of preference or "religion" - brackets serve a very specific purpose.

<?php
// try this (doesn't work: {}s DON'T concatenate!):
$var1 = 'hello ';
$var2 = 'world';
print {$var1}{$var2};

// now try this (NO concatenation):
print "{$var1}{$var2}";

// and this (concatenation):
print "$var1"."$var2";

// and, to mix things up:
$varArray = array( $var1,$var2 );
print "$varArray[0]$varArray[1]";  // ambiguous 
print "{$varArray[0]}{$varArray[1]}"; // not ambiguous

the purpose of the curly brackets is to resolve ambiguity. Take your earlier example:

// (missing sentences)
$sentence1 = "This is sentence one.";
$sentence4 = ". Sentence four includes the missing punctuation from sentence three, for some reason";

//  this is not concatenation: it's all *one* string.
"{$sentence1}Sentence 2 is here. Sentence 3 coming along{$sentence4}Now we have sentence 5.";
// without the {brackets}, PHP would look for the variable `$sentence1Sentence`,
//  because it doesn't know that `Sentence` is intended to be literal text.
//  the {brackets} mark which part is the variable.  

// Similarly, in this example, the brackets are *completely unnecessary*:
"{$sentence1} Sentence 2 has leading whitespace. Sentence 3 coming along{$sentence4}-Now we have sentence 5.";
// try it without them
print "$sentence1 Sentence 2 has leading whitespace. Sentence 3 coming along$sentence4-Now we have sentence 5.";