I've seen a couple of questions which use a language which has the following chracters:
<>-+.[]
What language is that?
Quite possibly BrainF_ck (concerning the spelling), a minimal programing language and a exemplar of the Turing Tar Pit.
Fish and GolfScript are also contenders.... J is also possible. I've seen a lot of GolfScript because it allows for concise manipulation of arrays and such. Fish uses the above characters much more extensively than the others.... and I confess I don't know exactly what distinguishes J syntactically.
I believe that all of them fall into the category of the Turing Tar Pit as described by @dmckee
,
was not mentioned in the list in the question.
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