=== Introduction === CalcPHP is a math expression calculator write in PHP. I write it just for fun and programming language implement study purpose. It define and implement a small language to do calculation works. You can use it as a command line tool like : $ php CalcPHP.php CalcPHP command line interface V1.0 > 1. result: 1.000000 (0.000102 sec) > 1 + 2. result: 3.000000 (0.000133 sec) > 1 + 2 * 3. result: 7.000000 (0.000426 sec) > 1 + 2 * 3 / 4. result: 2.500000 (0.000357 sec) > (1 + 2) * (3 / 4). result: 2.250000 (0.000329 sec) > a = 1, b = 2, c = 3, (a + b) / c. result: 1.000000 (0.000782 sec) > add = fun(a, b) -> a + b end. result: 1.000000 (0.000448 sec) > add(10, 20). result: 30.000000 (0.000431 sec) > exit And you can embed CalcPHP in your app by include "CalcPHP.php", and use it like: //create global state $state = new CalcState(); //create a parser $parser = new CalcParser($code, $state); //parse code as AST $doc = $parser->Parse(); //execute AST and get result $result = $doc->Exec();