Hello !
Coming from Make so i’m a little bit in trouble, i would like to extract phone numbers from an email, i have the right regex and (i think) the right code javascript but i don’t know how to make it work in n8n,
Could someone help me ?
Thanks a lot 
Hi @Lilian_Sevoumian, welcome to the community 
This error message is indeed not very helpful from looking at your code, sorry for that.
My suggestion here would be to take a look at the example snippet n8n provides when adding a new Code node to your workflow. It returns a valid item using the n8n data structure. An example workflow using .test() would look like so:
You can also use regular expressions without writing code (beyond the expression) in the IF node: