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Reminds me a bit of dc:

https://en.wikipedia.org/wiki/Dc_%28computer_program%29

People who are interested in low-level language implementation might wish to learn a little dc, because its ability to easily produce arbitrary binary output may come in handy when boostrapping.

There was that old RSA in a sig file...

    #!/bin/perl -sp0777i<X+d*lMLa^*lN%0]dsXx++lMlN/dsM0<j]dsj
    $/=unpack('H*',$_);$_=`echo 16dio\U$k"SK$/SM$n\EsN0p[lN*1
    lK[d2%Sa2/d0$^Ixp"|dc`;s/\W//g;$_=pack('H*',/((..)*)$/)

You'll note on that last line a |dc` as all of that stuff after the `echo` gets packed into something for dc to run.

http://www.cypherspace.org/adam/rsa/rsa-details.html

Thank you for linking this! Went down a 2-hour rabbit hole and it's really scratching some sort of itch.

It is exceedingly terse. Every command is a single character and the only required formatting is a single space to separate numbers. Just this side of line noise...

bc is built on dc and uses infix notation.

bc -l supports arbitrary-precision arithmetic, IIRC.

`k` in dc sets the fractional digits after the dot.

I am not sure there is a limit but 99 works ...

Good to know, can be useful.

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