After reading the Custom Web Publishing Guide and all the old threads here on send_email and using concat to embed a field reference, I'm still getting an error message. I'd love some advice:

code:

...

error message:

java.lang.NoSuchMethodException: For extension function, could not find method com.fmi.xslt.ExtensionFunctions.send_email([ExpressionContext,] #STRING). Checked both static and instance methods.

(XSLT)

I did read in one thread something about an additional template needed, but I didn't understand the logic or if it applied in my case. Currently, this send_email function is at the end of a form that uses a hidden input to edit one field in the default record, send the email, then move on to the next page.

Thanks in advance for your help.

You just placed the brackets wrong. Figure out from the corrected solution:

Thank you so much, Martin. I can't believe I missed that. I really appreciate your help.