# Online error "\_Blank\_ is not a constructor"
**URL:** https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453
**Category:** Online experiments
**Tags:** online, coding, pavlovia
**Created:** [October 19, 2022, 6:44pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453 "2022-10-19T18:44:21Z")
**Posts on this page:** 11
**Page:** 1
### Author:  [@aboye](https://discourse.psychopy.org/u/aboye)
#### Post date: [October 19, 2022, 6:44pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/1 "2022-10-19T18:44:21Z")
URL of experiment: [DietCognitions SONA [PsychoPy]](https://run.pavlovia.org/aboye/tasknewassoc/)
Description of the problem:
Hi. I am not an experienced coder. I coped a task that works online exactly as is onto my task. I am getting the error “core.Clock is not a constructor”. Please help. Thank you in advance.
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### Author:  [@wakecarter](https://discourse.psychopy.org/u/wakecarter)
#### Post date: [October 19, 2022, 7:28pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/2 "2022-10-19T19:28:14Z")
As per my crib sheet core.Clock() should be manually translated to new util.Clock()
> **[PsychoPy Python to Javascript crib sheet 2021](https://docs.google.com/document/d/183xmwDgSbnJZHMGf3yWpieV9Bx8y7fOCm3QKkMOOXFQ/edit)**
>
> PsychoPy version 2021.1.3-2021.2.3Python to JavaScript Crib Sheet Compiled by Wakefield Morys-Carter, Oxford Brookes UniversityPlease share widely and follow Psych\_Stats on twitter. PsychoPy 2021 is a major update with several new features. When...
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### Author:  [@aboye](https://discourse.psychopy.org/u/aboye)
#### Post date: [October 19, 2022, 7:56pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/3 "2022-10-19T19:56:15Z")
Hello,
I have replaced “core.Clock()” with “util.Clock()” and the problem persists. Thanks.
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### Author:  [@wakecarter](https://discourse.psychopy.org/u/wakecarter)
#### Post date: [October 19, 2022, 8:00pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/4 "2022-10-19T20:00:02Z")
Your experiment still contains
```auto
timing = new core.Clock();
```
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### Author:  [@aboye](https://discourse.psychopy.org/u/aboye)
#### Post date: [October 19, 2022, 8:22pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/5 "2022-10-19T20:22:09Z")
Hi, I have looked through all of the codes that are implemented in this task many times and I do not see it there. I attached two screenshots where it has the new code. I made sure this was synced with the online version and the problem persists. Thank you.
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### Author:  [@wakecarter](https://discourse.psychopy.org/u/wakecarter)
#### Post date: [October 19, 2022, 8:30pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/6 "2022-10-19T20:30:04Z")
You are showing a Python (Py) code component. Switch it to Auto to create the JS and then to Both if you need to edit the JS.
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### Author:  [@aboye](https://discourse.psychopy.org/u/aboye)
#### Post date: [October 20, 2022, 2:50pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/7 "2022-10-20T14:50:10Z")
Thank you for the help, that solved that issue. Now I get this error.
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### Author:  [@wakecarter](https://discourse.psychopy.org/u/wakecarter)
#### Post date: [October 20, 2022, 2:59pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/8 "2022-10-20T14:59:24Z")
Have a look at the Developer console to see the line giving the error.
[https://psychopy.org/online/psychoJSCodingDebugging.html](https://psychopy.org/online/psychoJSCodingDebugging.html)
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### Author:  [@aboye](https://discourse.psychopy.org/u/aboye)
#### Post date: [October 20, 2022, 3:48pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/9 "2022-10-20T15:48:13Z")
Hi,
It looks like this is causing the error. Thanks.
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### Author:  [@aboye](https://discourse.psychopy.org/u/aboye)
#### Post date: [October 21, 2022, 10:10pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/10 "2022-10-21T22:10:51Z")
Do you have any idea how to solve this error?
Thanks.
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### Author:  [@wakecarter](https://discourse.psychopy.org/u/wakecarter)
#### Post date: [October 21, 2022, 10:19pm UTC](https://discourse.psychopy.org/t/online-error-blank-is-not-a-constructor/31453/11 "2022-10-21T22:19:59Z")
Try removing np.NAN since numpy doesn’t work online.
What I do is remove and replace lines a few at a time to narrow down the error.