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// guess the programming language of the day

$ whois brainfuck

Brainfuck

first released in 1993 · by Urban Müller

$ guessprog --inspect brainfuck

year: 1993
paradigm: imperative
family: other
memory: none
binding: static
safety: weak

BRAINFUCK(7)

AUTHORS: Urban Müller
HISTORY: Swiss student Urban Müller created Brainfuck in 1993 on the Amiga, with the goal of writing the smallest possible compiler; his original compiler was only a few hundred bytes. The language has just eight commands, each a single character, which move a pointer along an array of bytes, change values, loop and do input and output. Everything else in the source is ignored as a comment. Despite its minimalism it is Turing complete.
USAGE: Not used for real software. It is one of the best known esoteric languages, popular for programming puzzles, code golf and as a first exercise in writing interpreters.
SEE ALSO: Brainfuck on Wikipedia ↗

$ cat hello.bf

Prints Hello World followed by a newline
Any character that is not a command is a comment

++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]
>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.
>>+.>++.