On 7/10/18 4:57 PM, Isaac Marcos wrote: > Chet Ramey (<chet.ra...@case.edu <mailto:chet.ra...@case.edu>>) wrote: > > On 7/10/18 2:48 PM, Isaac Marcos wrote: > > That is not an integer constant. Integer constants don't begin > with `-'. > > > That makes negative numbers invalid.
You need to look at the difference between constants and operators. This is what allows you to write $(( -a )), for instance. > Because of the difference between an operator and a constant. Unary plus > and minus have a higher precedence than arithmetic operators. So if you > expand the `a' to an expression, which is what happens, the expression > consists of an operator (+ or -) and a constant, and that expression has > a higher precedence than the +. You might think about why using `$a' in > place of the `a' would not work all the time. > > > > I don't care. All other shells do this correctly. It makes you the only one > wrong. "All other shells" is kind of a broad statement. -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRU c...@case.edu http://tiswww.cwru.edu/~chet/