How to append a statement using the null coalesce operator to a string?












2















I have a string with an operator in:



echo 'abc.' . $type ?? 'no type' . 'xyz';


If $type exists I want that to be the value, if it does not, I want 'no type' to be the value.



But with the above I just get a $type undefined error. It's not defined in my example as I want 'no type' to be outputted.



Where am I going wrong?






php php-7







share|improve this question




















  • 1





    We can start by asking which version of PHP you're using, since ?? is a relatively new operator.

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:25













  • I'm using PHP 7.

    – panthro
    Nov 19 '18 at 18:27






  • 1





    Please also update your question to mention that. No one should have to read a comment thread to answer your question =) Also, did you make sure to read through the operator precedence list? secure.php.net/manual/en/language.operators.precedence.php (specifically, you want to look at which of . and ?? gets to go first)

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:29


















2















I have a string with an operator in:



echo 'abc.' . $type ?? 'no type' . 'xyz';


If $type exists I want that to be the value, if it does not, I want 'no type' to be the value.



But with the above I just get a $type undefined error. It's not defined in my example as I want 'no type' to be outputted.



Where am I going wrong?






php php-7







share|improve this question




















  • 1





    We can start by asking which version of PHP you're using, since ?? is a relatively new operator.

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:25













  • I'm using PHP 7.

    – panthro
    Nov 19 '18 at 18:27






  • 1





    Please also update your question to mention that. No one should have to read a comment thread to answer your question =) Also, did you make sure to read through the operator precedence list? secure.php.net/manual/en/language.operators.precedence.php (specifically, you want to look at which of . and ?? gets to go first)

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:29
















2












2








2


0






I have a string with an operator in:



echo 'abc.' . $type ?? 'no type' . 'xyz';


If $type exists I want that to be the value, if it does not, I want 'no type' to be the value.



But with the above I just get a $type undefined error. It's not defined in my example as I want 'no type' to be outputted.



Where am I going wrong?






php php-7







share|improve this question
















I have a string with an operator in:



echo 'abc.' . $type ?? 'no type' . 'xyz';


If $type exists I want that to be the value, if it does not, I want 'no type' to be the value.



But with the above I just get a $type undefined error. It's not defined in my example as I want 'no type' to be outputted.



Where am I going wrong?






php php-7




php php-7






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Nov 19 '18 at 18:44









miken32

23.7k84972




23.7k84972










asked Nov 19 '18 at 18:23









panthropanthro

7,04332100202




7,04332100202








  • 1





    We can start by asking which version of PHP you're using, since ?? is a relatively new operator.

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:25













  • I'm using PHP 7.

    – panthro
    Nov 19 '18 at 18:27






  • 1





    Please also update your question to mention that. No one should have to read a comment thread to answer your question =) Also, did you make sure to read through the operator precedence list? secure.php.net/manual/en/language.operators.precedence.php (specifically, you want to look at which of . and ?? gets to go first)

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:29
















  • 1





    We can start by asking which version of PHP you're using, since ?? is a relatively new operator.

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:25













  • I'm using PHP 7.

    – panthro
    Nov 19 '18 at 18:27






  • 1





    Please also update your question to mention that. No one should have to read a comment thread to answer your question =) Also, did you make sure to read through the operator precedence list? secure.php.net/manual/en/language.operators.precedence.php (specifically, you want to look at which of . and ?? gets to go first)

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:29










1




1





We can start by asking which version of PHP you're using, since ?? is a relatively new operator.

– Mike 'Pomax' Kamermans
Nov 19 '18 at 18:25







We can start by asking which version of PHP you're using, since ?? is a relatively new operator.

– Mike 'Pomax' Kamermans
Nov 19 '18 at 18:25















I'm using PHP 7.

– panthro
Nov 19 '18 at 18:27





I'm using PHP 7.

– panthro
Nov 19 '18 at 18:27




1




1





Please also update your question to mention that. No one should have to read a comment thread to answer your question =) Also, did you make sure to read through the operator precedence list? secure.php.net/manual/en/language.operators.precedence.php (specifically, you want to look at which of . and ?? gets to go first)

– Mike 'Pomax' Kamermans
Nov 19 '18 at 18:29







Please also update your question to mention that. No one should have to read a comment thread to answer your question =) Also, did you make sure to read through the operator precedence list? secure.php.net/manual/en/language.operators.precedence.php (specifically, you want to look at which of . and ?? gets to go first)

– Mike 'Pomax' Kamermans
Nov 19 '18 at 18:29














3 Answers
3






active

oldest

votes


















8














You need to add brackets round the ?? operator...



echo 'abc.' . ($type ?? 'no type') . 'xyz';


What it was doing was evaluating it like 'abc.' . $type and then ??.



This is all about operator precedence (thanks to @Blackhole for the prompt).






share|improve this answer


























  • A link to the documentation.

    – Blackhole
    Nov 19 '18 at 18:28











  • Thank you very much. Will accept asap.

    – panthro
    Nov 19 '18 at 18:29



















1














Null Coalescing Operator:



echo 'abc.' . ($type ?? 'no type') . 'xyz';


or this (ternary operator)



echo 'abc.' . (isset($type) ? $type : 'no type' ) . 'xyz';





share|improve this answer


























  • That's not really a userful answer in this case, though. Using ?? is fine, but . has higher precedence, so the ?? expression needs to be in parentheses.

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:31





















0














You don't need to use concatenation when using echo. It can take multiple arguments, just separate them with a comma (as if it were an actual function):



echo 'abc.', $type ?? 'no type', 'xyz';


This is also (slightly) more efficient than the upvoted answer, especially with long strings (PHP doesn't have to construct/store the whole string in a buffer before displaying it).






share|improve this answer

























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    3 Answers
    3






    active

    oldest

    votes








    3 Answers
    3






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    8














    You need to add brackets round the ?? operator...



    echo 'abc.' . ($type ?? 'no type') . 'xyz';


    What it was doing was evaluating it like 'abc.' . $type and then ??.



    This is all about operator precedence (thanks to @Blackhole for the prompt).






    share|improve this answer


























    • A link to the documentation.

      – Blackhole
      Nov 19 '18 at 18:28











    • Thank you very much. Will accept asap.

      – panthro
      Nov 19 '18 at 18:29
















    8














    You need to add brackets round the ?? operator...



    echo 'abc.' . ($type ?? 'no type') . 'xyz';


    What it was doing was evaluating it like 'abc.' . $type and then ??.



    This is all about operator precedence (thanks to @Blackhole for the prompt).






    share|improve this answer


























    • A link to the documentation.

      – Blackhole
      Nov 19 '18 at 18:28











    • Thank you very much. Will accept asap.

      – panthro
      Nov 19 '18 at 18:29














    8












    8








    8







    You need to add brackets round the ?? operator...



    echo 'abc.' . ($type ?? 'no type') . 'xyz';


    What it was doing was evaluating it like 'abc.' . $type and then ??.



    This is all about operator precedence (thanks to @Blackhole for the prompt).






    share|improve this answer















    You need to add brackets round the ?? operator...



    echo 'abc.' . ($type ?? 'no type') . 'xyz';


    What it was doing was evaluating it like 'abc.' . $type and then ??.



    This is all about operator precedence (thanks to @Blackhole for the prompt).







    share|improve this answer














    share|improve this answer



    share|improve this answer








    edited Nov 19 '18 at 18:30

























    answered Nov 19 '18 at 18:27









    Nigel RenNigel Ren

    26.6k61833




    26.6k61833













    • A link to the documentation.

      – Blackhole
      Nov 19 '18 at 18:28











    • Thank you very much. Will accept asap.

      – panthro
      Nov 19 '18 at 18:29



















    • A link to the documentation.

      – Blackhole
      Nov 19 '18 at 18:28











    • Thank you very much. Will accept asap.

      – panthro
      Nov 19 '18 at 18:29

















    A link to the documentation.

    – Blackhole
    Nov 19 '18 at 18:28





    A link to the documentation.

    – Blackhole
    Nov 19 '18 at 18:28













    Thank you very much. Will accept asap.

    – panthro
    Nov 19 '18 at 18:29





    Thank you very much. Will accept asap.

    – panthro
    Nov 19 '18 at 18:29













    1














    Null Coalescing Operator:



    echo 'abc.' . ($type ?? 'no type') . 'xyz';


    or this (ternary operator)



    echo 'abc.' . (isset($type) ? $type : 'no type' ) . 'xyz';





    share|improve this answer


























    • That's not really a userful answer in this case, though. Using ?? is fine, but . has higher precedence, so the ?? expression needs to be in parentheses.

      – Mike 'Pomax' Kamermans
      Nov 19 '18 at 18:31


















    1














    Null Coalescing Operator:



    echo 'abc.' . ($type ?? 'no type') . 'xyz';


    or this (ternary operator)



    echo 'abc.' . (isset($type) ? $type : 'no type' ) . 'xyz';





    share|improve this answer


























    • That's not really a userful answer in this case, though. Using ?? is fine, but . has higher precedence, so the ?? expression needs to be in parentheses.

      – Mike 'Pomax' Kamermans
      Nov 19 '18 at 18:31
















    1












    1








    1







    Null Coalescing Operator:



    echo 'abc.' . ($type ?? 'no type') . 'xyz';


    or this (ternary operator)



    echo 'abc.' . (isset($type) ? $type : 'no type' ) . 'xyz';





    share|improve this answer















    Null Coalescing Operator:



    echo 'abc.' . ($type ?? 'no type') . 'xyz';


    or this (ternary operator)



    echo 'abc.' . (isset($type) ? $type : 'no type' ) . 'xyz';






    share|improve this answer














    share|improve this answer



    share|improve this answer








    edited Nov 19 '18 at 18:40









    Jay Blanchard

    35.6k125596




    35.6k125596










    answered Nov 19 '18 at 18:25









    Kamil KiełczewskiKamil Kiełczewski

    10.1k86093




    10.1k86093













    • That's not really a userful answer in this case, though. Using ?? is fine, but . has higher precedence, so the ?? expression needs to be in parentheses.

      – Mike 'Pomax' Kamermans
      Nov 19 '18 at 18:31





















    • That's not really a userful answer in this case, though. Using ?? is fine, but . has higher precedence, so the ?? expression needs to be in parentheses.

      – Mike 'Pomax' Kamermans
      Nov 19 '18 at 18:31



















    That's not really a userful answer in this case, though. Using ?? is fine, but . has higher precedence, so the ?? expression needs to be in parentheses.

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:31







    That's not really a userful answer in this case, though. Using ?? is fine, but . has higher precedence, so the ?? expression needs to be in parentheses.

    – Mike 'Pomax' Kamermans
    Nov 19 '18 at 18:31













    0














    You don't need to use concatenation when using echo. It can take multiple arguments, just separate them with a comma (as if it were an actual function):



    echo 'abc.', $type ?? 'no type', 'xyz';


    This is also (slightly) more efficient than the upvoted answer, especially with long strings (PHP doesn't have to construct/store the whole string in a buffer before displaying it).






    share|improve this answer






























      0














      You don't need to use concatenation when using echo. It can take multiple arguments, just separate them with a comma (as if it were an actual function):



      echo 'abc.', $type ?? 'no type', 'xyz';


      This is also (slightly) more efficient than the upvoted answer, especially with long strings (PHP doesn't have to construct/store the whole string in a buffer before displaying it).






      share|improve this answer




























        0












        0








        0







        You don't need to use concatenation when using echo. It can take multiple arguments, just separate them with a comma (as if it were an actual function):



        echo 'abc.', $type ?? 'no type', 'xyz';


        This is also (slightly) more efficient than the upvoted answer, especially with long strings (PHP doesn't have to construct/store the whole string in a buffer before displaying it).






        share|improve this answer















        You don't need to use concatenation when using echo. It can take multiple arguments, just separate them with a comma (as if it were an actual function):



        echo 'abc.', $type ?? 'no type', 'xyz';


        This is also (slightly) more efficient than the upvoted answer, especially with long strings (PHP doesn't have to construct/store the whole string in a buffer before displaying it).







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited Nov 19 '18 at 19:15

























        answered Nov 19 '18 at 18:54









        JetoJeto

        5,22521018




        5,22521018






























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