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Update evalwise.class.php #258

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40 changes: 18 additions & 22 deletions reports/evalwise.class.php
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Original file line number Diff line number Diff line change
Expand Up @@ -56,36 +56,33 @@ public function set_data($data): void {
* pfx
*
* @param array|bool $tokens
* @param array $vars
* @param mixed $vars
* @return array|false|mixed|null
*/
public function pfx($tokens, array $vars = []) {

public function pfx($tokens, $vars = []) {
if ($tokens === false) {
return false;
}

$stack = new EvalMathStack;

foreach ($tokens as $token) {

// If the token is a function, pop arguments off the stack, hand them to the function, and push the result back on.
// If the token is a function, pop arguments off the stack, hand them to the function, and push the result back on
if (is_array($token)) {

// It's a function!
$fnn = $token['fnn'];
$count = $token['argcount'];

if (in_array($fnn, $this->fb)) { // Built-in function.
if (in_array($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.
$fnn = preg_replace("/^arc/", "a", $fnn); // For the 'arc' trig synonyms
if ($fnn === 'ln') {
$fnn = 'log';
}

// TODO Use the PHP internal function if possible.
// TODO Use the PHP internal function if possible
// @codingStandardsIgnoreStart
/*
evaluate postfix notation
Expand All @@ -94,11 +91,11 @@ public function pfx($tokens, array $vars = []) {
+ => | => array_merge
- => ^ => array_diff
*/
eval('$stack->push(' . $fnn . '($op1));'); // Perfectly safe eval().
eval('$stack->push(' . $fnn . '($op1));'); // Perfectly safe eval()
// @codingStandardsIgnoreEnd

} else if (array_key_exists($fnn, $this->fc)) { // Calc emulation function.
// Get args.
} else if (array_key_exists($fnn, $this->fc)) { // Calc emulation function
// Get args
$args = [];
for ($i = $count - 1; $i >= 0; $i--) {
if (is_null($args[] = $stack->pop())) {
Expand All @@ -110,21 +107,21 @@ public function pfx($tokens, array $vars = []) {
return $this->trigger("internal error");
}
$stack->push($res);
} else if (array_key_exists($fnn, $this->f)) {
// User function.
// Get args.

} else if (array_key_exists($fnn, $this->f)) { // User function
// Get args
$args = [];
for ($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');
}
}

// Yay recursion!
$stack->push($this->pfx($this->f[$fnn]['func'], $args));
}

} else if (in_array($token, ['+', '-', '*', '/', '^'], true)) {
// If the token is a binary operator, pop two values off the stack, do the operation, and push the result back on.
// If the token is a binary operator, pop two values off the stack, do the operation, and push the result back on
if (is_null($op2 = $stack->pop())) {
return $this->trigger('internal error');
}
Expand All @@ -151,10 +148,10 @@ public function pfx($tokens, array $vars = []) {
}

} else if ($token === "_") {
// If the token is a unary operator, pop one value off the stack, do the operation, and push it back on.
// If the token is a unary operator, pop one value off the stack, do the operation, and push it back on
$stack->push(-1 * $stack->pop());
} else {
// If the token is a number or variable, push it on the stack.
// If the token is a number or variable, push it on the stack
if (is_numeric($token)) {
$stack->push($token);
} else if (array_key_exists($token, $this->v)) {
Expand All @@ -166,14 +163,13 @@ public function pfx($tokens, array $vars = []) {
}
}
}
// When we're out of tokens, the stack should have a single element, the final result.

// 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");
}

$last = $stack->pop();

return $this->data[$last] ?? false;
}

}