diff --git a/includes/math-expr.inc b/includes/math-expr.inc index eeb184d..01f2788 100644 --- a/includes/math-expr.inc +++ b/includes/math-expr.inc @@ -1,388 +1,551 @@ - -================================================================================ - -NAME - ctools_math_expr - safely evaluate math expressions - -SYNOPSIS - include('ctools_math_expr.class.php'); - $m = new ctools_math_expr; - // basic evaluation: - $result = $m->evaluate('2+2'); - // supports: order of operation; parentheses; negation; built-in functions - $result = $m->evaluate('-8(5/2)^2*(1-sqrt(4))-8'); - // create your own variables - $m->evaluate('a = e^(ln(pi))'); - // or functions - $m->evaluate('f(x,y) = x^2 + y^2 - 2x*y + 1'); - // and then use them - $result = $m->evaluate('3*f(42,a)'); - -DESCRIPTION - Use the ctools_math_expr class when you want to evaluate mathematical expressions - from untrusted sources. You can define your own variables and functions, - which are stored in the object. Try it, it's fun! - -METHODS - $m->evalute($expr) - Evaluates the expression and returns the result. If an error occurs, - prints a warning and returns false. If $expr is a function assignment, - returns true on success. - - $m->e($expr) - A synonym for $m->evaluate(). - - $m->vars() - Returns an associative array of all user-defined variables and values. - - $m->funcs() - Returns an array of all user-defined functions. - -PARAMETERS - $m->suppress_errors - Set to true to turn off warnings when evaluating expressions - - $m->last_error - If the last evaluation failed, contains a string describing the error. - (Useful when suppress_errors is on). - -AUTHOR INFORMATION - Copyright 2005, Miles Kaufmann. - -LICENSE - Redistribution and use in source and binary forms, with or without - modification, are permitted provided that the following conditions are - met: - - 1 Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - 2. Redistributions in binary form must reproduce the above copyright - notice, this list of conditions and the following disclaimer in the - documentation and/or other materials provided with the distribution. - 3. The name of the author may not be used to endorse or promote - products derived from this software without specific prior written - permission. - - THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR - IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED - WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE - DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, - INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES - (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR - SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, - STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN - ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE - POSSIBILITY OF SUCH DAMAGE. - -*/ class ctools_math_expr { - var $suppress_errors = false; - var $last_error = null; - - var $v = array('e'=>2.71,'pi'=>3.14); // variables (and constants) - var $f = array(); // user-defined functions - var $vb = array('e', 'pi'); // constants - var $fb = array( // built-in functions - 'sin','sinh','arcsin','asin','arcsinh','asinh', - 'cos','cosh','arccos','acos','arccosh','acosh', - 'tan','tanh','arctan','atan','arctanh','atanh', - 'pow', 'exp', - 'sqrt','abs','ln','log', - 'time', 'ceil', 'floor', 'min', 'max', 'round'); - - function ctools_math_expr() { - // make the variables a little more accurate - $this->v['pi'] = pi(); - $this->v['e'] = exp(1); - drupal_alter('ctools_math_expression_functions', $this->fb); + var $suppress_errors = FALSE; + var $last_error = NULL; + var $errors = array(); + + var $v = array('e' => 2.71, 'pi' => 3.14); // variables (and constants) + var $f = array(); // user-defined functions + var $vb = array('e', 'pi'); // constants + var $fsimple = array( // built-in functions + 'sin', 'sinh', 'asin', 'asinh', + 'cos', 'cosh', 'acos', 'acosh', + 'tan', 'tanh', 'atan', 'atanh', + 'exp', + 'sqrt', 'abs', 'log', + 'time', 'ceil', 'floor', 'round' + ); + var $fb = array( + 'ln' => array( + 'function' => 'log', + 'arguments' => 1, + ), + 'arcsin' => array( + 'function' => 'asin', + 'arguments' => 1, + ), + 'arcsinh' => array( + 'function' => 'asinh', + 'arguments' => 1, + ), + 'arccos' => array( + 'function' => 'acos', + 'arguments' => 1, + ), + 'arccosh' => array( + 'function' => 'acosh', + 'arguments' => 1, + ), + 'arctan' => array( + 'function' => 'atan', + 'arguments' => 1, + ), + 'arctanh' => array( + 'function' => 'atanh', + 'arguments' => 1, + ), + 'min' => array( + 'function' => 'min', + 'arguments' => 2, + 'max arguments' => 99, + ), + 'max' => array( + 'function' => 'max', + 'arguments' => 2, + 'max arguments' => 99, + ), + 'pow' => array( + 'function' => 'pow', + 'arguments' => 2, + ), + 'if' => array( + 'function' => 'ctools_math_expr_if', + 'arguments' => 2, + 'max arguments' => 3, + ), + 'number' => array( + 'function' => 'ctools_math_expr_number', + 'arguments' => 1, + ), + ); + + /** + * Public constructor. + */ + public function __construct() { + // Make the variables a little more accurate. + $this->v['pi'] = pi(); + $this->v['e'] = exp(1); + + // Allow modules to add custom functions. + // @todo -- properly document this. + $context = array('final' => &$this->fb); + drupal_alter('ctools_math_expression_functions', $this->fsimple, $context); + + // Translate the older, simpler style into the newer, richer style. + foreach ($this->fsimple as $function) { + $this->fb[$function] = array( + 'function' => $function, + 'arguments' => 1, + ); } + } + + /** + * Evaluate the expression. + * + * @param string $expr The expression to evaluate. + * @return string + */ + function evaluate($expr) { + $this->last_error = NULL; + $expr = trim($expr); + if (substr($expr, -1, 1) == ';') { + $expr = substr($expr, 0, strlen($expr) - 1); + } // strip semicolons at the end + + // is it a variable assignment? + if (preg_match('/^\s*([a-z]\w*)\s*=\s*(.+)$/', $expr, $matches)) { + if (in_array($matches[1], $this->vb)) { // make sure we're not assigning to a constant + return $this->trigger("cannot assign to constant '$matches[1]'"); + } + if (($tmp = $this->pfx($this->nfx($matches[2]))) === FALSE) { + return FALSE; + } // get the result and make sure it's good + $this->v[$matches[1]] = $tmp; // if so, stick it in the variable array + return $this->v[$matches[1]]; // and return the resulting value + + // is it a function assignment? + } + elseif (preg_match('/^\s*([a-z]\w*)\s*\(\s*([a-z]\w*(?:\s*,\s*[a-z]\w*)*)\s*\)\s*=\s*(.+)$/', $expr, $matches)) { + $fnn = $matches[1]; // get the function name + if (isset($this->fb[$matches[1]])) { // make sure it isn't built in + return $this->trigger("cannot redefine built-in function '$matches[1]()'"); + } + $args = explode(",", preg_replace("/\s+/", "", $matches[2])); // get the arguments + if (($stack = $this->nfx($matches[3])) === FALSE) { + return FALSE; + } // see if it can be converted to postfix + for ($i = 0; $i < count($stack); $i++) { // freeze the state of the non-argument variables + $token = $stack[$i]; + if (preg_match('/^[a-z]\w*$/', $token) and !in_array($token, $args)) { + if (array_key_exists($token, $this->v)) { + $stack[$i] = $this->v[$token]; + } + else { + return $this->trigger("undefined variable '$token' in function definition"); + } + } + } + $this->f[$fnn] = array('args' => $args, 'func' => $stack); + + return TRUE; - function e($expr) { - return $this->evaluate($expr); + } + else { + return trim($this->pfx($this->nfx($expr)), '"'); // straight up evaluation, woo + } + } + + /** + * Fetch an array of variables used in the expression. + * + * @return array + */ + public function vars() { + $output = $this->v; + unset($output['pi']); + unset($output['e']); + + return $output; + } + + /** + * Fetch all user defined functions in the expression. + * + * @return array + */ + public function funcs() { + $output = array(); + foreach ($this->f as $fnn => $dat) { + $output[] = $fnn . '(' . implode(',', $dat['args']) . ')'; } - function evaluate($expr) { - $this->last_error = null; - $expr = trim($expr); - if (substr($expr, -1, 1) == ';') $expr = substr($expr, 0, strlen($expr)-1); // strip semicolons at the end - //=============== - // is it a variable assignment? - if (preg_match('/^\s*([a-z]\w*)\s*=\s*(.+)$/', $expr, $matches)) { - if (in_array($matches[1], $this->vb)) { // make sure we're not assigning to a constant - return $this->trigger("cannot assign to constant '$matches[1]'"); - } - if (($tmp = $this->pfx($this->nfx($matches[2]))) === false) return false; // get the result and make sure it's good - $this->v[$matches[1]] = $tmp; // if so, stick it in the variable array - return $this->v[$matches[1]]; // and return the resulting value - //=============== - // is it a function assignment? - } elseif (preg_match('/^\s*([a-z]\w*)\s*\(\s*([a-z]\w*(?:\s*,\s*[a-z]\w*)*)\s*\)\s*=\s*(.+)$/', $expr, $matches)) { - $fnn = $matches[1]; // get the function name - if (in_array($matches[1], $this->fb)) { // make sure it isn't built in - return $this->trigger("cannot redefine built-in function '$matches[1]()'"); + return $output; + } + + // Convert infix to postfix notation + private function nfx($expr) { + + $index = 0; + $stack = new ctools_math_expr_stack; + $output = array(); // postfix form of expression, to be passed to pfx() + $expr = trim(strtolower($expr)); + + $ops = array( + '+' => array( + 'precedence' => 0, + ), + '-' => array( + 'precedence' => 0, + ), + '*'=> array( + 'precedence' => 1, + ), + '/'=> array( + 'precedence' => 1, + ), + '^' => array( + 'right' => TRUE, + 'precedence' => 2, + ), + '_' => array( + 'precedence' => 1, + ), + '==' => array( + 'precedence' => -1, + ), + '!=' => array( + 'precedence' => -1, + ), + '>=' => array( + 'precedence' => -1, + ), + '<=' => array( + 'precedence' => -1, + ), + '>' => array( + 'precedence' => -1, + ), + '<' => array( + 'precedence' => -1, + ) + ); + $expecting_op = FALSE; // we use this in syntax-checking the expression + // And determining when a - is a negation + + while (1) { // 1 Infinite Loop ;) + $op = substr($expr, $index, 1); // get the first character at the current index + // if the second character is an =, add it to our op. + if (substr($expr, $index + 1, 1) == '=') { + $op = substr($expr, $index, 2); + $index++; + } + // find out if we're currently at the beginning of a number/variable/function/parenthesis/operand + $ex = preg_match('/^([a-z]\w*\(?|\d+(?:\.\d*)?|\.\d+|\()/', substr($expr, $index), $match); + + if ($op == '-' and !$expecting_op) { // is it a negation instead of a minus? + $stack->push('_'); // put a negation on the stack + $index++; + } + elseif ($op == '_') { // we have to explicitly deny this, because it's legal on the stack + return $this->trigger("illegal character '_'"); // but not in the input expression + + } + elseif ((isset($ops[$op]) || $ex) && $expecting_op) { // are we putting an operator on the stack? + if ($ex) { // are we expecting an operator but have a number/variable/function/opening parenthesis? + $op = '*'; + $index--; // it's an implicit multiplication + } + // heart of the algorithm: + while ($stack->count > 0 && ($o2 = $stack->last()) && isset($ops[$o2]) && (!empty($ops[$op]['right']) ? $ops[$op]['precedence'] < $ops[$o2]['precedence'] : $ops[$op]['precedence'] <= $ops[$o2]['precedence'])) { + $output[] = $stack->pop(); // pop stuff off the stack into the output + } + // many thanks: http://en.wikipedia.org/wiki/Reverse_Polish_notation#The_algorithm_in_detail + $stack->push($op); // finally put OUR operator onto the stack + $index++; + $expecting_op = FALSE; + + } + elseif ($op == ')' and $expecting_op) { // ready to close a parenthesis? + while (($o2 = $stack->pop()) != '(') { // pop off the stack back to the last ( + if (is_null($o2)) { + return $this->trigger("unexpected ')'"); + } + else { + $output[] = $o2; + } + } + if (preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) { // did we just close a function? + $fnn = $matches[1]; // get the function name + $arg_count = $stack->pop(); // see how many arguments there were (cleverly stored on the stack, thank you) + $output[] = $stack->pop(); // pop the function and push onto the output + if (isset($this->fb[$fnn])) { // check the argument count + $max_arguments = isset($this->fb[$fnn]['max arguments']) ? $this->fb[$fnn]['max arguments'] : $this->fb[$fnn]['arguments']; + if ($arg_count > $max_arguments) { + return $this->trigger("too many arguments ($arg_count given, $max_arguments expected)"); } - $args = explode(",", preg_replace("/\s+/", "", $matches[2])); // get the arguments - if (($stack = $this->nfx($matches[3])) === false) return false; // see if it can be converted to postfix - for ($i = 0; $iv)) { - $stack[$i] = $this->v[$token]; - } else { - return $this->trigger("undefined variable '$token' in function definition"); - } - } + } + elseif (array_key_exists($fnn, $this->f)) { + if ($arg_count != count($this->f[$fnn]['args'])) { + return $this->trigger("wrong number of arguments ($arg_count given, " . count($this->f[$fnn]['args']) . " expected)"); } - $this->f[$fnn] = array('args'=>$args, 'func'=>$stack); - return true; - //=============== - } else { - return $this->pfx($this->nfx($expr)); // straight up evaluation, woo + } + else { // did we somehow push a non-function on the stack? this should never happen + return $this->trigger("internal error"); + } } + $index++; + + } + elseif ($op == ',' and $expecting_op) { // did we just finish a function argument? + while (($o2 = $stack->pop()) != '(') { + if (is_null($o2)) { + return $this->trigger("unexpected ',' in $expr $o2"); + } // oops, never had a ( + else { + $output[] = $o2; + } // pop the argument expression stuff and push onto the output + } + // make sure there was a function + if (!preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) { + return $this->trigger("unexpected ','"); + } + $stack->push($stack->pop() + 1); // increment the argument count + $stack->push('('); // put the ( back on, we'll need to pop back to it again + $index++; + $expecting_op = FALSE; + + } + elseif ($op == '(' and !$expecting_op) { + $stack->push('('); // that was easy + $index++; + $allow_neg = TRUE; + + } + elseif ($ex and !$expecting_op) { // do we now have a function/variable/number? + $expecting_op = TRUE; + $val = $match[1]; + if (preg_match("/^([a-z]\w*)\($/", $val, $matches)) { // may be func, or variable w/ implicit multiplication against parentheses... + if (isset($this->fb[$matches[1]]) or array_key_exists($matches[1], $this->f)) { // it's a func + $stack->push($val); + $stack->push(1); + $stack->push('('); + $expecting_op = FALSE; + } + else { // it's a var w/ implicit multiplication + $val = $matches[1]; + $output[] = $val; + } + } + else { // it's a plain old var or num + $output[] = $val; + } + $index += strlen($val); + + } + elseif ($op == ')') { // miscellaneous error checking + return $this->trigger("unexpected ')'"); + } + elseif (isset($ops[$op]) and !$expecting_op) { + return $this->trigger("unexpected operator '$op'"); + } + elseif ($op == '"') { + // fetch a quoted string. + $string = substr($expr, $index); + if (preg_match('/"[^"\\\\]*(?:\\\\.[^"\\\\]*)*"/s', $string, $matches)) { + $string = $matches[0]; + // trim the quotes off: + $output[] = $string; + $index += strlen($string); + $expecting_op = TRUE; + } + else { + return $this->trigger("open quote without close quote."); + } + } + else { // I don't even want to know what you did to get here + return $this->trigger("an unexpected error occurred at $op"); + } + if ($index == strlen($expr)) { + if (isset($ops[$op])) { // did we end with an operator? bad. + return $this->trigger("operator '$op' lacks operand"); + } + else { + break; + } + } + while (substr($expr, $index, 1) == ' ') { // step the index past whitespace (pretty much turns whitespace + $index++; // into implicit multiplication if no operator is there) + } } - - function vars() { - $output = $this->v; - unset($output['pi']); - unset($output['e']); - return $output; - } - - function funcs() { - $output = array(); - foreach ($this->f as $fnn=>$dat) - $output[] = $fnn . '(' . implode(',', $dat['args']) . ')'; - return $output; + while (!is_null($op = $stack->pop())) { // pop everything off the stack and push onto output + if ($op == '(') { + return $this->trigger("expecting ')'"); + } // if there are (s on the stack, ()s were unbalanced + $output[] = $op; } - //===================== HERE BE INTERNAL METHODS ====================\\ + return $output; + } - // Convert infix to postfix notation - function nfx($expr) { + // evaluate postfix notation + function pfx($tokens, $vars = array()) { - $index = 0; - $stack = new ctools_math_expr_stack; - $output = array(); // postfix form of expression, to be passed to pfx() - $expr = trim(strtolower($expr)); - - $ops = array('+', '-', '*', '/', '^', '_'); - $ops_r = array('+'=>0,'-'=>0,'*'=>0,'/'=>0,'^'=>1); // right-associative operator? - $ops_p = array('+'=>0,'-'=>0,'*'=>1,'/'=>1,'_'=>1,'^'=>2); // operator precedence + if ($tokens == FALSE) { + return FALSE; + } - $expecting_op = false; // we use this in syntax-checking the expression - // and determining when a - is a negation + $stack = new ctools_math_expr_stack; - if (preg_match("/[^\w\s+*^\/()\.,-]/", $expr, $matches)) { // make sure the characters are all good - return $this->trigger("illegal character '{$matches[0]}'"); + foreach ($tokens as $token) { // nice and easy + // if the token is a binary operator, pop two values off the stack, do the operation, and push the result back on + if (in_array($token, array('+', '-', '*', '/', '^', '==', '!=', '<', '<=', '>=', '>'))) { + if (is_null($op2 = $stack->pop())) { + return $this->trigger("internal error"); } - - while(1) { // 1 Infinite Loop ;) - $op = substr($expr, $index, 1); // get the first character at the current index - // find out if we're currently at the beginning of a number/variable/function/parenthesis/operand - $ex = preg_match('/^([a-z]\w*\(?|\d+(?:\.\d*)?|\.\d+|\()/', substr($expr, $index), $match); - //=============== - if ($op == '-' and !$expecting_op) { // is it a negation instead of a minus? - $stack->push('_'); // put a negation on the stack - $index++; - } elseif ($op == '_') { // we have to explicitly deny this, because it's legal on the stack - return $this->trigger("illegal character '_'"); // but not in the input expression - //=============== - } elseif ((in_array($op, $ops) or $ex) and $expecting_op) { // are we putting an operator on the stack? - if ($ex) { // are we expecting an operator but have a number/variable/function/opening parethesis? - $op = '*'; $index--; // it's an implicit multiplication - } - // heart of the algorithm: - while($stack->count > 0 and ($o2 = $stack->last()) and in_array($o2, $ops) and ($ops_r[$op] ? $ops_p[$op] < $ops_p[$o2] : $ops_p[$op] <= $ops_p[$o2])) { - $output[] = $stack->pop(); // pop stuff off the stack into the output - } - // many thanks: http://en.wikipedia.org/wiki/Reverse_Polish_notation#The_algorithm_in_detail - $stack->push($op); // finally put OUR operator onto the stack - $index++; - $expecting_op = false; - //=============== - } elseif ($op == ')' and $expecting_op) { // ready to close a parenthesis? - while (($o2 = $stack->pop()) != '(') { // pop off the stack back to the last ( - if (is_null($o2)) return $this->trigger("unexpected ')'"); - else $output[] = $o2; - } - if (preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) { // did we just close a function? - $fnn = $matches[1]; // get the function name - $arg_count = $stack->pop(); // see how many arguments there were (cleverly stored on the stack, thank you) - $output[] = $stack->pop(); // pop the function and push onto the output - if (in_array($fnn, $this->fb)) { // check the argument count - if($arg_count > 1) - return $this->trigger("too many arguments ($arg_count given, 1 expected)"); - } elseif (array_key_exists($fnn, $this->f)) { - if ($arg_count != count($this->f[$fnn]['args'])) - return $this->trigger("wrong number of arguments ($arg_count given, " . count($this->f[$fnn]['args']) . " expected)"); - } else { // did we somehow push a non-function on the stack? this should never happen - return $this->trigger("internal error"); - } - } - $index++; - //=============== - } elseif ($op == ',' and $expecting_op) { // did we just finish a function argument? - while (($o2 = $stack->pop()) != '(') { - if (is_null($o2)) return $this->trigger("unexpected ','"); // oops, never had a ( - else $output[] = $o2; // pop the argument expression stuff and push onto the output - } - // make sure there was a function - if (!preg_match("/^([a-z]\w*)\($/", $stack->last(2), $matches)) - return $this->trigger("unexpected ','"); - $stack->push($stack->pop()+1); // increment the argument count - $stack->push('('); // put the ( back on, we'll need to pop back to it again - $index++; - $expecting_op = false; - //=============== - } elseif ($op == '(' and !$expecting_op) { - $stack->push('('); // that was easy - $index++; - $allow_neg = true; - //=============== - } elseif ($ex and !$expecting_op) { // do we now have a function/variable/number? - $expecting_op = true; - $val = $match[1]; - if (preg_match("/^([a-z]\w*)\($/", $val, $matches)) { // may be func, or variable w/ implicit multiplication against parentheses... - if (in_array($matches[1], $this->fb) or array_key_exists($matches[1], $this->f)) { // it's a func - $stack->push($val); - $stack->push(1); - $stack->push('('); - $expecting_op = false; - } else { // it's a var w/ implicit multiplication - $val = $matches[1]; - $output[] = $val; - } - } else { // it's a plain old var or num - $output[] = $val; - } - $index += strlen($val); - //=============== - } elseif ($op == ')') { // miscellaneous error checking - return $this->trigger("unexpected ')'"); - } elseif (in_array($op, $ops) and !$expecting_op) { - return $this->trigger("unexpected operator '$op'"); - } else { // I don't even want to know what you did to get here - return $this->trigger("an unexpected error occurred"); + if (is_null($op1 = $stack->pop())) { + return $this->trigger("internal error"); + } + switch ($token) { + case '+': + $stack->push($op1 + $op2); + break; + case '-': + $stack->push($op1 - $op2); + break; + case '*': + $stack->push($op1 * $op2); + break; + case '/': + if ($op2 == 0) { + return $this->trigger("division by zero"); } - if ($index == strlen($expr)) { - if (in_array($op, $ops)) { // did we end with an operator? bad. - return $this->trigger("operator '$op' lacks operand"); - } else { - break; - } + $stack->push($op1 / $op2); + break; + case '^': + $stack->push(pow($op1, $op2)); + break; + case '==': + $stack->push(intval($op1 == $op2)); + break; + case '!=': + $stack->push(intval($op1 != $op2)); + break; + case '<=': + $stack->push(intval($op1 <= $op2)); + break; + case '<': + $stack->push(intval($op1 < $op2)); + break; + case '>=': + $stack->push(intval($op1 >= $op2)); + break; + case '>': + $stack->push(intval($op1 > $op2)); + break; + } + // if the token is a unary operator, pop one value off the stack, do the operation, and push it back on + } + elseif ($token == "_") { + $stack->push(-1 * $stack->pop()); + // if the token is a function, pop arguments off the stack, hand them to the function, and push the result back on + } + elseif (preg_match("/^([a-z]\w*)\($/", $token, $matches)) { // it's a function! + $fnn = $matches[1]; + if (isset($this->fb[$fnn])) { // built-in function: + $args = array(); + for ($i = 0; $i < $this->fb[$fnn]['arguments']; $i++) { + if (is_null($op1 = $stack->pop())) { + return $this->trigger("function $fnn missing argument $i"); } - while (substr($expr, $index, 1) == ' ') { // step the index past whitespace (pretty much turns whitespace - $index++; // into implicit multiplication if no operator is there) + $args[] = $op1; + } + if (!empty($this->fb[$fnn]['max arguments'])) { + for(;$i < $this->fb[$fnn]['max arguments']; $i++) { + $arg = $stack->pop(); + if (!isset($arg)) { + break; + } + $args[] = $arg; } + } + $stack->push(call_user_func_array($this->fb[$fnn]['function'], array_reverse($args))); } - while (!is_null($op = $stack->pop())) { // pop everything off the stack and push onto output - if ($op == '(') return $this->trigger("expecting ')'"); // if there are (s on the stack, ()s were unbalanced - $output[] = $op; - } - return $output; - } - - // evaluate postfix notation - function pfx($tokens, $vars = array()) { - - if ($tokens == false) return false; - - $stack = new ctools_math_expr_stack; - - foreach ($tokens as $token) { // nice and easy - // if the token is a binary operator, pop two values off the stack, do the operation, and push the result back on - if (in_array($token, array('+', '-', '*', '/', '^'))) { - if (is_null($op2 = $stack->pop())) return $this->trigger("internal error"); - if (is_null($op1 = $stack->pop())) return $this->trigger("internal error"); - switch ($token) { - case '+': - $stack->push($op1+$op2); break; - case '-': - $stack->push($op1-$op2); break; - case '*': - $stack->push($op1*$op2); break; - case '/': - if ($op2 == 0) return $this->trigger("division by zero"); - $stack->push($op1/$op2); break; - case '^': - $stack->push(pow($op1, $op2)); break; - } - // if the token is a unary operator, pop one value off the stack, do the operation, and push it back on - } elseif ($token == "_") { - $stack->push(-1*$stack->pop()); - // if the token is a function, pop arguments off the stack, hand them to the function, and push the result back on - } elseif (preg_match("/^([a-z]\w*)\($/", $token, $matches)) { // it's a function! - $fnn = $matches[1]; - if (in_array($fnn, $this->fb)) { // built-in function: - if (is_null($op1 = $stack->pop())) return $this->trigger("internal error"); - $fnn = preg_replace("/^arc/", "a", $fnn); // for the 'arc' trig synonyms - if ($fnn == 'ln') $fnn = 'log'; - eval('$stack->push(' . $fnn . '($op1));'); // perfectly safe eval() - } elseif (array_key_exists($fnn, $this->f)) { // user function - // get args - $args = array(); - for ($i = count($this->f[$fnn]['args'])-1; $i >= 0; $i--) { - if (is_null($args[$this->f[$fnn]['args'][$i]] = $stack->pop())) return $this->trigger("internal error"); - } - $stack->push($this->pfx($this->f[$fnn]['func'], $args)); // yay... recursion!!!! - } - // if the token is a number or variable, push it on the stack - } else { - if (is_numeric($token)) { - $stack->push($token); - } elseif (array_key_exists($token, $this->v)) { - $stack->push($this->v[$token]); - } elseif (array_key_exists($token, $vars)) { - $stack->push($vars[$token]); - } else { - return $this->trigger("undefined variable '$token'"); - } + elseif (isset($fnn, $this->f)) { // user function + // get args + $args = array(); + for ($i = count($this->f[$fnn]['args']) - 1; $i >= 0; $i--) { + if (is_null($args[$this->f[$fnn]['args'][$i]] = $stack->pop())) { + return $this->trigger("internal error"); } + } + $stack->push($this->pfx($this->f[$fnn]['func'], $args)); // yay... recursion!!!! } - // when we're out of tokens, the stack should have a single element, the final result - if ($stack->count != 1) return $this->trigger("internal error"); - return $stack->pop(); + // if the token is a number or variable, push it on the stack + } + else { + if (is_numeric($token) || $token[0] == '"') { + $stack->push($token); + } + elseif (array_key_exists($token, $this->v)) { + $stack->push($this->v[$token]); + } + elseif (array_key_exists($token, $vars)) { + $stack->push($vars[$token]); + } + else { + return $this->trigger("undefined variable '$token'"); + } + } + } + // when we're out of tokens, the stack should have a single element, the final result + if ($stack->count != 1) { + return $this->trigger("internal error"); } - // trigger an error, but nicely, if need be - function trigger($msg) { - $this->last_error = $msg; - if (!$this->suppress_errors) trigger_error($msg, E_USER_WARNING); - return false; + return $stack->pop(); + } + + // trigger an error, but nicely, if need be + function trigger($msg) { + $this->errors[] = $msg; + $this->last_error = $msg; + if (!$this->suppress_errors) { + trigger_error($msg, E_USER_WARNING); } + + return FALSE; + } } // for internal use class ctools_math_expr_stack { - var $stack = array(); - var $count = 0; + var $stack = array(); + var $count = 0; - function push($val) { - $this->stack[$this->count] = $val; - $this->count++; - } + function push($val) { + $this->stack[$this->count] = $val; + $this->count++; + } - function pop() { - if ($this->count > 0) { - $this->count--; - return $this->stack[$this->count]; - } - return null; - } + function pop() { + if ($this->count > 0) { + $this->count--; - function last($n=1) { - return !empty($this->stack[$this->count-$n]) ? $this->stack[$this->count-$n] : NULL; + return $this->stack[$this->count]; } + + return NULL; + } + + function last($n = 1) { + return !empty($this->stack[$this->count - $n]) ? $this->stack[$this->count - $n] : NULL; + } } +function ctools_math_expr_if($expr, $if, $else = NULL) { + return $expr ? $if : $else; +} + +function ctools_math_expr_number($arg) { + // Remove any non-digits so that numbers like $4,511.23 still work. + // @todo: locale could break this sincein some locales that's $4.512,33 + // so there needs to be a way to detect that and make it work properly. + $arg = preg_replace("/[^0-9\.]/", '', $arg); + return $arg; +} diff --git a/tests/math_expression.test b/tests/math_expression.test index 730e079..cec975c 100644 --- a/tests/math_expression.test +++ b/tests/math_expression.test @@ -39,31 +39,31 @@ class CtoolsMathExpressionTestCase extends DrupalWebTestCase { $math_expression = new ctools_math_expr(); // Test constant expressions. - $this->assertEqual($math_expression->e('2'), 2); + $this->assertEqual($math_expression->evaluate('2'), 2); $random_number = rand(0, 10); - $this->assertEqual($random_number, $math_expression->e((string) $random_number)); + $this->assertEqual($random_number, $math_expression->evaluate((string) $random_number)); // Test simple arithmetic. $random_number_a = rand(5, 10); $random_number_b = rand(5, 10); - $this->assertEqual($random_number_a + $random_number_b, $math_expression->e("$random_number_a + $random_number_b")); - $this->assertEqual($random_number_a - $random_number_b, $math_expression->e("$random_number_a - $random_number_b")); - $this->assertEqual($random_number_a * $random_number_b, $math_expression->e("$random_number_a * $random_number_b")); - $this->assertEqual($random_number_a / $random_number_b, $math_expression->e("$random_number_a / $random_number_b")); + $this->assertEqual($random_number_a + $random_number_b, $math_expression->evaluate("$random_number_a + $random_number_b")); + $this->assertEqual($random_number_a - $random_number_b, $math_expression->evaluate("$random_number_a - $random_number_b")); + $this->assertEqual($random_number_a * $random_number_b, $math_expression->evaluate("$random_number_a * $random_number_b")); + $this->assertEqual(round($random_number_a / $random_number_b, 8), round($math_expression->evaluate("$random_number_a / $random_number_b"), 8)); // Test Associative property. $random_number_c = rand(5, 10); - $this->assertEqual($math_expression->e("$random_number_a + ($random_number_b + $random_number_c)"), $math_expression->e("($random_number_a + $random_number_b) + $random_number_c")); - $this->assertEqual($math_expression->e("$random_number_a * ($random_number_b * $random_number_c)"), $math_expression->e("($random_number_a * $random_number_b) * $random_number_c")); + $this->assertEqual($math_expression->evaluate("$random_number_a + ($random_number_b + $random_number_c)"), $math_expression->evaluate("($random_number_a + $random_number_b) + $random_number_c")); + $this->assertEqual($math_expression->evaluate("$random_number_a * ($random_number_b * $random_number_c)"), $math_expression->evaluate("($random_number_a * $random_number_b) * $random_number_c")); // Test Commutative property. - $this->assertEqual($math_expression->e("$random_number_a + $random_number_b"), $math_expression->e("$random_number_b + $random_number_a")); - $this->assertEqual($math_expression->e("$random_number_a * $random_number_b"), $math_expression->e("$random_number_b * $random_number_a")); + $this->assertEqual($math_expression->evaluate("$random_number_a + $random_number_b"), $math_expression->evaluate("$random_number_b + $random_number_a")); + $this->assertEqual($math_expression->evaluate("$random_number_a * $random_number_b"), $math_expression->evaluate("$random_number_b * $random_number_a")); // Test Distributive property. - $this->assertEqual($math_expression->e("($random_number_a + $random_number_b) * $random_number_c"), $math_expression->e("($random_number_a * $random_number_c + $random_number_b * $random_number_c)")); + $this->assertEqual($math_expression->evaluate("($random_number_a + $random_number_b) * $random_number_c"), $math_expression->evaluate("($random_number_a * $random_number_c + $random_number_b * $random_number_c)")); - $this->assertEqual(pow($random_number_a, $random_number_b), $math_expression->e("$random_number_a ^ $random_number_b")); + $this->assertEqual(pow($random_number_a, $random_number_b), $math_expression->evaluate("$random_number_a ^ $random_number_b")); } public function testBuildInFunctions() { @@ -72,26 +72,25 @@ class CtoolsMathExpressionTestCase extends DrupalWebTestCase { // @todo: maybe run this code multiple times to test different values. $random_double = $this->rand01(); $random_int = rand(5, 10); - $this->assertFloat(sin($random_double), $math_expression->e("sin($random_double)")); - $this->assertFloat(cos($random_double), $math_expression->e("cos($random_double)")); - $this->assertFloat(tan($random_double), $math_expression->e("tan($random_double)")); - $this->assertFloat(exp($random_double), $math_expression->e("exp($random_double)")); - $this->assertFloat(sqrt($random_double), $math_expression->e("sqrt($random_double)")); - $this->assertFloat(log($random_double), $math_expression->e("ln($random_double)")); - $this->assertFloat(round($random_double), $math_expression->e("round($random_double)")); - $this->assertFloat(abs($random_double + $random_int), $math_expression->e('abs(' . ($random_double + $random_int) . ')')); - $this->assertEqual(round($random_double + $random_int), $math_expression->e('round(' . ($random_double + $random_int) . ')')); - $this->assertEqual(ceil($random_double + $random_int), $math_expression->e('ceil(' . ($random_double + $random_int) . ')')); - $this->assertEqual(floor($random_double + $random_int), $math_expression->e('floor(' . ($random_double + $random_int) . ')')); + $this->assertFloat(sin($random_double), $math_expression->evaluate("sin($random_double)")); + $this->assertFloat(cos($random_double), $math_expression->evaluate("cos($random_double)")); + $this->assertFloat(tan($random_double), $math_expression->evaluate("tan($random_double)")); + $this->assertFloat(exp($random_double), $math_expression->evaluate("exp($random_double)")); + $this->assertFloat(sqrt($random_double), $math_expression->evaluate("sqrt($random_double)")); + $this->assertFloat(log($random_double), $math_expression->evaluate("ln($random_double)")); + $this->assertFloat(round($random_double), $math_expression->evaluate("round($random_double)")); + $this->assertFloat(abs($random_double + $random_int), $math_expression->evaluate('abs(' . ($random_double + $random_int) . ')')); + $this->assertEqual(round($random_double + $random_int), $math_expression->evaluate('round(' . ($random_double + $random_int) . ')')); + $this->assertEqual(ceil($random_double + $random_int), $math_expression->evaluate('ceil(' . ($random_double + $random_int) . ')')); + $this->assertEqual(floor($random_double + $random_int), $math_expression->evaluate('floor(' . ($random_double + $random_int) . ')')); // @fixme: you can't run time without an argument. - $this->assertFloat(time(), $math_expression->e('time(1)')); + $this->assertFloat(time(), $math_expression->evaluate('time(1)')); $random_double_a = $this->rand01(); $random_double_b = $this->rand01(); - // @fixme: max/min don't work at the moment. -// $this->assertFloat(max($random_double_a, $random_double_b), $math_expression->e("max($random_double_a, $random_double_b)")); -// $this->assertFloat(min($random_double_a, $random_double_b), $math_expression->e("min($random_double_a, $random_double_b)")); + $this->assertFloat(max($random_double_a, $random_double_b), $math_expression->evaluate("max($random_double_a, $random_double_b)")); + $this->assertFloat(min($random_double_a, $random_double_b), $math_expression->evaluate("min($random_double_a, $random_double_b)")); } public function testVariables() { @@ -101,11 +100,11 @@ class CtoolsMathExpressionTestCase extends DrupalWebTestCase { $random_number_b = rand(5, 10); // Store the first random number and use it on calculations. - $math_expression->e("var = $random_number_a"); - $this->assertEqual($random_number_a + $random_number_b, $math_expression->e("var + $random_number_b")); - $this->assertEqual($random_number_a * $random_number_b, $math_expression->e("var * $random_number_b")); - $this->assertEqual($random_number_a - $random_number_b, $math_expression->e("var - $random_number_b")); - $this->assertEqual($random_number_a / $random_number_b, $math_expression->e("var / $random_number_b")); + $math_expression->evaluate("var = $random_number_a"); + $this->assertEqual($random_number_a + $random_number_b, $math_expression->evaluate("var + $random_number_b")); + $this->assertEqual($random_number_a * $random_number_b, $math_expression->evaluate("var * $random_number_b")); + $this->assertEqual($random_number_a - $random_number_b, $math_expression->evaluate("var - $random_number_b")); + $this->assertEqual(round($random_number_a / $random_number_b, 8), round($math_expression->evaluate("var / $random_number_b"), 8)); } public function testCustomFunctions() { @@ -115,15 +114,31 @@ class CtoolsMathExpressionTestCase extends DrupalWebTestCase { $random_number_b = rand(5, 10); // Create a one-argument function. - $math_expression->e("f(x) = 2 * x"); - $this->assertEqual($random_number_a * 2, $math_expression->e("f($random_number_a)")); - $this->assertEqual($random_number_b * 2, $math_expression->e("f($random_number_b)")); + $math_expression->evaluate("f(x) = 2 * x"); + $this->assertEqual($random_number_a * 2, $math_expression->evaluate("f($random_number_a)")); + $this->assertEqual($random_number_b * 2, $math_expression->evaluate("f($random_number_b)")); // Create a two-argument function. - $math_expression->e("g(x, y) = 2 * x + y"); - $this->assertEqual($random_number_a * 2 + $random_number_b, $math_expression->e("g($random_number_a, $random_number_b)")); + $math_expression->evaluate("g(x, y) = 2 * x + y"); + $this->assertEqual($random_number_a * 2 + $random_number_b, $math_expression->evaluate("g($random_number_a, $random_number_b)")); // Use a custom function in another function. - $this->assertEqual(($random_number_a * 2 + $random_number_b) * 2, $math_expression->e("f(g($random_number_a, $random_number_b))")); + $this->assertEqual(($random_number_a * 2 + $random_number_b) * 2, $math_expression->evaluate("f(g($random_number_a, $random_number_b))")); } + + public function testIf() { + $math_expression = new ctools_math_expr(); + + $random_number_a = rand(1, 5); + $random_number_b = rand(10, 20); + + $this->assertEqual($math_expression->evaluate("if(1, $random_number_a, $random_number_b)"), $random_number_a); + $this->assertEqual($math_expression->evaluate("if(1, $random_number_a)"), $random_number_a); + + $this->assertEqual($math_expression->evaluate("if(0, $random_number_a, $random_number_b)"), $random_number_b); + + // Also add an expression so ensure it's evaluated. + $this->assertEqual($math_expression->evaluate("if($random_number_a > $random_number_b, $random_number_a, $random_number_b)"), $random_number_b); + } + }