#!/usr/bin/perl
#$Id: calcme,v 1.4 2001/10/04 18:00:57 mstorti Exp $

$input=shift;
# require "$ENV{'HOME'}/perl/math.pl";

if ($input eq "-h") {
    print <<'EOM';

CALCME: a simple (Perl based) line calculator

usage : 
* Compute an expression (remember to enclose <expression> in quotes or double quotes 
   in order to avoid shell expansion )

    $ calc <expression> 
    <result>

* Interactive use: 
    $ calc
    > <expression>
    <result>
    > <expression>
    <result>
    ...
  
	Can define variables as in;
    > $pi=atan(1,0)*2
    
    > $pi=atan2(1,0)*2
    3.14159265358979
    > $e=exp(1)
    2.71828182845905
    > $a=$pi*$e**2
    23.2134043573634
    > 
             
* Get help (prints this message):
    $ calc -u               
EOM
    goto EXIT;
}

@ans=();

do {print "> ",eval $input,"\n"; goto EXIT;
} if $input;

print "> ";
while (<STDIN>) {
    print $ans=eval(),"\n> ";
    unshift @ans,$ans;
}

EXIT: ;