Re: expr shouldn't use spaces

[Carl Edquist]

On Mon, 19 Dec 2022, David Chmelik wrote:

> >  If the shell arithmetic is not sufficient, then I'd recommend bc(1).
> Thanks!  I was looking for that.  I don't know whether bc or calc is 
> better...

But, do try out the built-in shell arithmetic, too.  (Eg, under 
"Arithmetic Expansion" and "ARITHMETIC EVALUATION" in the bash manpage.)

Basically anything in double-parens (( )) gets treated like integer math 
in C (you can even skip the $ prefix for variables), and $(( )) is the 
same but you can use the result as a string in your command line.

It doesn't handle floating-point (while bc(1) does), but if all you want 
is expr(1) math without needing spaces, the shell does just fine.

Carl