how do tell delta what language a file is in?

[simonLeary42]

bat has something called --map-syntax to set the syntax of a file using a regex on the file path. does delta have an equivalent?

#1230 says that delta uses filename to detect langauge. does it exclusively use filename or does it fall back on any other mechanism?

[th1000s]

When a known file extension is found it is always used for highlighting, otherwise --default-language can change the fallback from txt to another language. So far mapping are not supported, but it sounds like a good idea.