Template language - Conditionally including text

[tgiladi]

Hi,
I followed the instructions here: https://manual.calibre-ebook.com/template_lang.html and successfully managed to set the save to disk setting to my preferences:

{series} {series_index:0>2s|#| - }{title} - {authors}

This works very well when saving to disk, so I thought I could use the same technique when customizing my jacket.xhtml template. What I am trying to achieve is having the book's name in it's original language, below the Ttitle. For this I am using a custom column, and I am able to show it without issue if there is data in that column. But what I can't figure out how to do is to have that name in parenthesis like so: (original name). If I add parenthesis to the code, then they would show anyway, even if there is no data in the custom column. I tried this code:

{_original_name:|(|)}

but it is not working and I get an error when I try to polish the book with this code: ValueError: Invalid format specifier '|(|)' for object of type 'str'

Is there another way to include the parenthesis around the conditional text only if there is data in the custom column?

[chaley]

Originally Posted by tgiladi

Hi,
I followed the instructions here: https://manual.calibre-ebook.com/template_lang.html and successfully managed to set the save to disk setting to my preferences:

{series} {series_index:0>2s|#| - }{title} - {authors}

This works very well when saving to disk, so I thought I could use the same technique when customizing my jacket.xhtml template. What I am trying to achieve is having the book's name in it's original language, below the Ttitle. For this I am using a custom column, and I am able to show it without issue if there is data in that column. But what I can't figure out how to do is to have that name in parenthesis like so: (original name). If I add parenthesis to the code, then they would show anyway, even if there is no data in the custom column. I tried this code:

{_original_name:|(|)}

but it is not working and I get an error when I try to polish the book with this code: ValueError: Invalid format specifier '|(|)' for object of type 'str'

Is there another way to include the parenthesis around the conditional text only if there is data in the custom column?

I suspect the parser in the jacket processor is not handling the conditional formatting specification correctly. As a workaround, put the parenthesis into your custom column. Or create a new "column built from other columns" that formats the text however you want.

[tgiladi]

Thank you for your suggestions! I opted for the custom column built from another column and formatted it to include the parenthesis. This is what I am including in my jacket now and it works exactly as I wanted it.