How do I echo the value of a variable before the code which calculates that value has been executed?

How do I echo the value of a variable before the code which calculates that value has been executed?

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I want to show a content of variable whom been calculate in a foreach loop. The problem is that I want to echo it before the loop.

    echo $total; // note this line I want to appear the total count of loop. the problem is it cannot appear because it is in the above of foreach loop. I want to appear it in this above before foreach loop.
    $total = 0;
    foreach($pathList as $item) {
        $fileInfo = pathinfo($item);
        if(preg_match(strtolower('/\b'.$_POST['song'].'\b/'), strtolower($filename))) {
            $total = $total + 1; // the total count of foreach loop I want to appear in echo $total    
        // some code

I do want to echo it inside the loop but only once after completed the loop. Any idea how do I solve this problem? I tried global $total but not working...

Thanks in advance!

Generally - NO. You cannot echo variable that not been calculate yet (synchronization in PHP).

If all you do in the for-loop regarding $total is increasing by 1 then you actually count the number of element in the array so you can just do:

echo count($pathList);

Before the for-loop. Documentation in here


If $total is affected in the loop (as you updated the question) then I believe best practice will be to counting array element first (without executing any more code), then echo the $total, afterward, loop on the original data and execute the rest of your code.

$total = 0;
foreach($pathList as $item) {
   $fileInfo = pathinfo($item);
   if(preg_match(strtolower('/\b'.$_POST['song'].'\b/'), strtolower($filename))) // or what ever condition you have to check for total
       $total = $total + 1;
echo count($total); // give you the count you need
foreach($pathList as $item) {
    // exec the rest of your code

This may run at O(2*n) but its not worse

Shell Scripting: Expert Recipes for Linux, Bash, and more, Some variables cannot be unset; these are referred to as the “read-only” Note that the first line of code accessed the myvar variable before it had been assigned a value, but no error was reported when the echo $myvar command was executed. Where is the bug in the following code to calculate the length of the  So, in your case, if you could change the total variable to total=$(cat t | wc -l), you should get only a number saved in the variable total. On the other hand, you can use cut or awk in order to extract the number part from the wc -l t part as follows: wc -l t | cut -d " " -f1. wc -l t | awk '{print $1}'

It is not possible. Lines are executed in the order in which they appear in the script.

Introduction to Pascal and Structured Design, board feet, so the step is correct and the calculated value is printed. We have to change the main module so that Code = 'P' is True before Calculate that data has been input to the five variables, and that Code contains the letter 'P' before Read Code, Size 1, Size2, Size 3, NumCrdered Echo-print input data IF Code is  Note there isn’t a space before or after the equals sign. Giving a variable a value is often referred to as assigning a value to the variable. We’ll create four string variables and one numeric variable, this_year: me=Dave my_boost=Linux him=Popeye his_boost=Spinach this_year=2019. To see the value held in a variable, use the echo command.

The value of $total at the end of the loop is equal to the value of count($pathList)

If you need the value of the last iterated element of the $pathList before the execution of the loop, then it can be echoed as

echo $pathList[count($pathList)-1];

Beginning PHP5, The PHP code starts with the function (named calculator) to calculate the cost of our holiday: function It multiplies these three variables together and returns one value ($price), the total price of the hotel. Before executing the $city_modifier variable has been set to 0; if it hasn't, you can call the function within the echo()  Instead it has the value from before I executed the Sheet5.Cells(1, 1).Value = Sheet5.Cells(i, 1).Value statement at the beginning of the loop. I would then use the "set next statement" back to the CurNum = Sheet5.Cells(1, 12).Value and after pressing F8 to execute the line would see that the value had updated to the correct value.

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are an infinite loop because there is no iteration variable, Before you can update a variable, you have to initialize it, usually with a If the condition is false, exit the while statement and continue execution at the next statement. The body of the loop should change the value of one or more variables so smallest code, we removed all of the print statements so as to be equivalent  it uses one variable to specify multiple values and uses a portion of the script to each value. describe an until loop it repeats the commands between do and done as long as the tested condition is false.

2. Variables, expressions and statements, If you are not sure what type a value has, the interpreter can tell you. Python interprets 1,000,000 as a list of three items to be printed. If there is more than one statement, the results appear one at a time as the statements execute. in the place of an operand, it is replaced with its value before the operation is performed. Assign the average of the values in the variables a , b , and c to a variable avg . Assume that the variables a , b , and c have already been assigned a value, but do not assume that the values are all floating-point. The average should be a floating-point value.