2018.1

Note that ${template.name} still includes the extension of the
template file (.OL-template in the example above).
${template.nr}
An automatic sequence number belonging to the current output file.
It is automatically incremented for each new output file that gets
created when Separation has been selected in the Output Creation
preset.
It is possible to format the number using a pattern and locale. See
"Formatting date and number values " on page723, below.
${template.ext}
The extension that corresponds to the chosen output format (in
lower case).
For example, for PDF output, ${template.ext} would be pdf, for
PostScript output, ${template.ext} would return ps.
Note that ${template.ext} does not include a leading dot.
File
${file}
${file} is a shorthand for ${file.base}_
${file.nr,0000}.${file.ext}. It expands to an internally
generated file name with a four digit sequence number at the end.
The file extension is determined by the selected output format.
The 0000 in ${file.nr,0000} is a format pattern that takes care of
formatting the number with at least four digits including leading
zero's. See "Formatting date and number values " on page723,
below.
Example
When printing to PDF, ${file} could expand to
merged.5852941188491153960_0001.pdf.
${file.base} Expands to a unique, internally generated file name, without a
trailing dot or extension.
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