function call in double quote doesn't work

[datactrl]

With PHP 5, why doesn't it work as following. It always shows "--->" instead of "--->zzz".

$aa = "--->{${getName()}}";
echo $aa;
 
function getName(){
    return 'zzz';
}
 

Jack

[Atli]

Jack.

Please use [code] tags when posting your code examples.

[code=php] ... PHP code goes here ... [/code]

Thank you.
Moderator

[Atli]

You can only use variables, array elements and object properties inside double quotes.

But... you can use the return value of a function or a method to dynamically get a variable name.

Consider this:

function getVarName() {
    return 'zzz';
}
$zzz = 'Var value';
echo "Value of variable = {${getVarName()}}";
 
// Prints: Value of variable = Var value
 

See Variable variables to see how that works.

[datactrl]

Thank you so much, Moderator. I will remember to code php code before post. Now I understand how it works on functions return value in double quote. Why do I ask this is because I want to insert some values returned from functions in here-document. Now, only way to do is setting variables from functions then include those variables in here-document.
Jack