public function reduce(Context $ctx)
{
$this->stack = array();
$len = 0;
// While there are input tokens left
// Read the next token from input.
while ($t = array_shift($this->queue)) {
switch ($t->type) {
case Token::T_NUMBER:
case Token::T_IDENT:
// wert einer konstanten ermitteln
if ($t->type === Token::T_IDENT) {
$t = new Token(Token::T_NUMBER, $ctx->cs($t->value));
}
// If the token is a value or identifier
// Push it onto the stack.
$this->stack[] = $t;
++$len;
break;
case Token::T_PLUS:
case Token::T_MINUS:
case Token::T_UNARY_PLUS:
case Token::T_UNARY_MINUS:
case Token::T_TIMES:
case Token::T_DIV:
case Token::T_MOD:
case Token::T_POW:
case Token::T_NOT:
// It is known a priori that the operator takes n arguments.
$na = $this->argc($t);
// If there are fewer than n values on the stack
if ($len < $na) {
throw new RuntimeError('laufzeit fehler: zu wenig paramter für operator "' . $t->value . '" (' . $na . ' -> ' . $len . ')');
}
$rhs = array_pop($this->stack);
$lhs = null;
if ($na > 1) {
$lhs = array_pop($this->stack);
}
// if ($lhs) print "{$lhs->value} {$t->value} {$rhs->value}\n";
// else print "{$t->value} {$rhs->value}\n";
$len -= $na - 1;
// Push the returned results, if any, back onto the stack.
$this->stack[] = new Token(Token::T_NUMBER, $this->op($t->type, $lhs, $rhs));
break;
case Token::T_FUNCTION:
// function
$argc = $t->argc;
$argv = array();
$len -= $argc - 1;
for (; $argc > 0; --$argc) {
array_unshift($argv, array_pop($this->stack)->value);
}
// Push the returned results, if any, back onto the stack.
$this->stack[] = new Token(Token::T_NUMBER, $ctx->fn($t->value, $argv));
break;
default:
throw new RuntimeError('laufzeit fehler: unerwarteter token `' . $t->value . '`');
}
}
// If there is only one value in the stack
// That value is the result of the calculation.
if (count($this->stack) === 1) {
return array_pop($this->stack)->value;
}
// If there are more values in the stack
// (Error) The user input has too many values.
throw new RuntimeError('laufzeit fehler: zu viele werte im stack');
}
/**
* @expectedException \RR\Shunt\Exception\RuntimeError
*/
public function testCallNotsetConstantCausesException()
{
$context = new Context();
$context->cs('notdefinedfunction');
}
public function reduce(Context $ctx)
{
$this->reset();
$this->stack = array();
$len = 0;
// While there are input tokens left
// Read the next token from input.
while ($t = array_shift($this->queue)) {
switch ($t->type) {
case Token::T_NUMBER:
case Token::T_NULL:
case Token::T_IDENT:
// determine constant value
if ($t->type === Token::T_IDENT) {
$t = new Token(Token::T_NUMBER, $ctx->cs($t->value));
}
// If the token is a value, null or identifier
// Push it onto the stack.
$this->stack[] = $t;
++$len;
break;
case Token::T_AND:
case Token::T_OR:
case Token::T_XOR:
case Token::T_GREATER_EQUAL:
case Token::T_LESS_EQUAL:
case Token::T_GREATER:
case Token::T_LESS:
case Token::T_EQUAL:
case Token::T_NOT_EQUAL:
case Token::T_PLUS:
case Token::T_MINUS:
case Token::T_UNARY_PLUS:
case Token::T_UNARY_MINUS:
case Token::T_TIMES:
case Token::T_DIV:
case Token::T_MOD:
case Token::T_POW:
case Token::T_NOT:
// It is known a priori that the operator takes n arguments.
$na = $this->argc($t);
// If there are fewer than n values on the stack
if ($len < $na) {
throw new RuntimeError('run-time error: too few parameters for operator "' . $t->value . '" (' . $na . ' -> ' . $len . ')');
}
$rhs = array_pop($this->stack);
$lhs = null;
if ($na > 1) {
$lhs = array_pop($this->stack);
}
// if ($lhs) print "{$lhs->value} {$t->value} {$rhs->value}\n";
// else print "{$t->value} {$rhs->value}\n";
$len -= $na - 1;
// Push the returned results, if any, back onto the stack.
$operationResult = $this->op($t->type, $lhs, $rhs, $ctx);
$this->stack[] = new Token(is_null($operationResult) ? Token::T_NULL : Token::T_NUMBER, $operationResult);
break;
case Token::T_FUNCTION:
// function
$argc = $t->argc;
$argv = array();
$len -= $argc - 1;
for (; $argc > 0; --$argc) {
array_unshift($argv, array_pop($this->stack)->value);
}
// Push the returned results, if any, back onto the stack.
$this->stack[] = new Token(Token::T_NUMBER, $ctx->fn($t->value, $argv));
break;
default:
throw new RuntimeError('run-time error: unexpected token `' . $t->value . '`');
}
}
// If there is only one value in the stack
// That value is the result of the calculation.
if (count($this->stack) == 1) {
return array_pop($this->stack)->value;
} elseif (count($this->stack) == 0) {
// Empty formula given
return null;
}
// If there are more values in the stack
// (Error) The user input has too many values.
throw new RuntimeError('run-time error: too many values in the stack');
}
