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Your LimeSurvey version: Version 5.2.5
Own server or LimeSurvey hosting: LimeSurvey hosting
Theme: skelvanilla

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Hello, 
My team and I encounter a big issue while using several surveys on Lime Survey: questions are unstable and randomly change, even when we are not using the survey itself. 

Exemple of change: 

• The label of a question is replaced by the label of another question
• The label of a line in an array is replaced by the label of another question

Here is an exemple of error we have seen, within a survey in both german and french language: 
 

Important: every times it happens, the old label is replaced by a new one from a question label with an ExpressionScript. 

Is there a way to prevent these random changes? Are ExpressionScript unstable and need to be avoid? 

Thanks in advance ! 

ExpressionScript is very stable.

You are paying LimeSurvey GmbH for hosting so...

1) Try using a core theme.

2) If the problem persists, contact LimeSurvey support directly.

And clearly : i don't see why it can happen with SkelVanilla

That was not a statement about the GREAT SkelVanilla theme. Just checking all of the boxes.

tpartner wrote:

That was not a statement about the GREAT SkelVanilla theme. Just checking all of the boxes.
 

Contacted via support email

Else : www.limesurvey.org/manual/Check_data_integrity

Hello,

Thanks for your answers. We tried to use another theme (Vanilla) and to correct all error message from “check data integrity”, but the issue is still persistent. Thus, it does not seem to occur due to the theme or data integrity.


Every time a question is move to another one, the new text that replace the old one is from a question with an ExpressionScript. We thus wonder if we misused it or if ExpressionScript are unstable.


The ExpressionScripts we use in this survey are often of this type (check of the participant age) :

<span class="custom-warnings" style="color:#c0392b;">{if((V5Q2tab_V5Q2 == 9) && (regexMatch('/^([1-9]|10)$/', V118a_other) || (is_empty(V118a_other))),"", if((V5Q2tab_V5Q2 == && (regexMatch('/^([1-9]|[1][0-1])$/', V118a_other) || (is_empty(V118a_other))),"", if((V5Q2tab_V5Q2 == 1) && (regexMatch('/^([1-9]|[1][0-8])$/', V118a_other) || (is_empty(V118a_other))),"",if((V5Q2tab_V5Q2 == 2) && (regexMatch('/^([1-9]|[1][0-7])$/', V118a_other) || (is_empty(V118a_other))),"",if((V5Q2tab_V5Q2 == 3) && (regexMatch('/^([1-9]|[1][0-6])$/', V118a_other) || (is_empty(V118a_other))),"",if((V5Q2tab_V5Q2 == 4) && (regexMatch('/^([1-9]|[1][0-5])$/', V118a_other) || (is_empty(V118a_other))),"",if((V5Q2tab_V5Q2 == 5) && (regexMatch('/^([1-9]|[1][0-4])$/', V118a_other) || (is_empty(V118a_other))),"",if((V5Q2tab_V5Q2 == 6) && (regexMatch('/^([1-9]|[1][0-3])$/', V118a_other) || (is_empty(V118a_other))),"",if((V5Q2tab_V5Q2 == 7) && (regexMatch('/^([1-9]|[1][0-2])$/', V118a_other) || (is_empty(V118a_other))),"",if(is_empty(V5Q2tab_V5Q2) && (regexMatch('/^([1-9]|[1][0-8])$/', V118a_other) || (is_empty(V118a_other))),"","Merci d'entrer un âge inférieur ou égal au tien"))))))))))}</span>

In this code the variable are:

• V5Q2tab_V5Q2 : year of birth from 2004 to 2012 (coded 1 to 9)
• V118a_other : age at the event X

And the custom.css code associated with the new class “custom-warnings” is:.custom-warnings{
    font-family: Verdana, sans-serif;
    font-size:14px;
    font-weight:bold;
}



The only code in custom.js is the following: 

$(document).ready(function() {
    $(document).find("input:checked[type='radio']").addClass('bounce');   
    $("input[type='radio']").click(function() {
        $(this).prop('checked', false);
        $(this).toggleClass('bounce');

        if( $(this).hasClass('bounce') ) {
            $(this).prop('checked', true);
            $(document).find("input:not(:checked)[type='radio']").removeClass('bounce');
        }
    });
});


Of note, all the ExpressionScript we use have the class “custom-warnings”.If it is of any help, here is a list of option we use in the survey: 

• Conditions (hide or not a question based on user answer)
• ExpressionScript (show a message if answers seem incoherent)
• Custom.css and custom.js in the theme code
• Survey in two langage (german and french)
• Several survey with same question group

Thanks in advance for your help 

As I said, you are a paying customer, if you have a problem you can contact LS support directly - account.limesurvey.org/customer-support

Can't you shorten your equation to something like

{if((intval(V118a_other) le (19-V5Q2tab_V5Q2)) OR is_empty(V118a_other),"","Merci d'entrer un âge inférieur ou égal au tien")}