private static function evaluateLiterals(&$tokenStream)
{
for ($i = 0; $i < count($tokenStream); $i++) {
$node = $tokenStream[$i];
if ($node->type != ExpType::$RAW) {
continue;
}
$str = strtolower($node->value);
if ($str == 'true' || $str == 'false') {
$tokenStream[$i] = ExpType::coerceToBool($node);
} elseif ($str == 'null') {
$tokenStream[$i] = ExpType::coerceToNull($node);
} elseif (preg_match(ExpLexer::$NUMBER_PATTERN, $str) == 1) {
$tokenStream[$i] = ExpType::coerceToNumber($node);
} elseif (preg_match(ExpLexer::$IDENTITY_PATTERN, $str) == 1) {
// is identity
$tokenStream[$i]->type = ExpType::$IDENTITY;
} else {
// mal-format
throw new ExpLexerException("Mal-format expression segment: " . $node->value);
}
}
}
/**
* Tests ExpType::coerce
*/
public function testCoerce()
{
// coerce number
$this->assertEquals($this->tokens['int'], ExpType::coerceToNumber($this->tokens['int']));
$this->assertEquals($this->tokens['float'], ExpType::coerceToNumber($this->tokens['float']));
$this->assertEquals(new Token(ExpType::$INT, 2), ExpType::coerceToNumber(new Token(ExpType::$RAW, '2')));
$this->assertEquals(new Token(ExpType::$INT, 2), ExpType::coerceToNumber(new Token(ExpType::$STRING, '2')));
$this->assertEquals(new Token(ExpType::$INT, 1), ExpType::coerceToNumber(new Token(ExpType::$BOOL, true)));
$this->assertEquals(new Token(ExpType::$INT, 0), ExpType::coerceToNumber(new Token(ExpType::$BOOL, false)));
$this->assertEquals(new Token(ExpType::$INT, 0), ExpType::coerceToNumber(new Token(ExpType::$NULL, null)));
$this->assertEquals(new Token(ExpType::$FLOAT, 1.0), ExpType::coerceToNumber(new Token(ExpType::$RAW, '1.0')));
$this->assertEquals(new Token(ExpType::$FLOAT, 1.0), ExpType::coerceToNumber(new Token(ExpType::$STRING, '1.0')));
// coerce string
$this->assertEquals($this->tokens['string'], ExpType::coerceToString($this->tokens['string']));
$this->assertEquals(new Token(ExpType::$STRING, '2'), ExpType::coerceToString(new Token(ExpType::$RAW, '2')));
$this->assertEquals(new Token(ExpType::$STRING, '2'), ExpType::coerceToString(new Token(ExpType::$INT, 2)));
$this->assertEquals(new Token(ExpType::$STRING, '2'), ExpType::coerceToString(new Token(ExpType::$FLOAT, 2.0)));
$this->assertEquals(new Token(ExpType::$STRING, '2.5'), ExpType::coerceToString(new Token(ExpType::$FLOAT, 2.5)));
$this->assertEquals(new Token(ExpType::$STRING, 'true'), ExpType::coerceToString(new Token(ExpType::$BOOL, true)));
$this->assertEquals(new Token(ExpType::$STRING, 'false'), ExpType::coerceToString(new Token(ExpType::$BOOL, false)));
$this->assertEquals(new Token(ExpType::$STRING, 'null'), ExpType::coerceToString(new Token(ExpType::$NULL, null)));
// coerce bool
$this->assertEquals($this->tokens['bool'], ExpType::coerceToBool($this->tokens['bool']));
$this->assertEquals(new Token(ExpType::$BOOL, true), ExpType::coerceToBool(new Token(ExpType::$RAW, 'True')));
$this->assertEquals(new Token(ExpType::$BOOL, true), ExpType::coerceToBool(new Token(ExpType::$RAW, 'true')));
$this->assertEquals(new Token(ExpType::$BOOL, false), ExpType::coerceToBool(new Token(ExpType::$RAW, 'False')));
$this->assertEquals(new Token(ExpType::$BOOL, false), ExpType::coerceToBool(new Token(ExpType::$RAW, 'false')));
$this->assertEquals(new Token(ExpType::$BOOL, true), ExpType::coerceToBool(new Token(ExpType::$STRING, 'false')));
$this->assertEquals(new Token(ExpType::$BOOL, false), ExpType::coerceToBool(new Token(ExpType::$STRING, '')));
$this->assertEquals(new Token(ExpType::$BOOL, true), ExpType::coerceToBool(new Token(ExpType::$INT, 2)));
$this->assertEquals(new Token(ExpType::$BOOL, false), ExpType::coerceToBool(new Token(ExpType::$INT, 0)));
$this->assertEquals(new Token(ExpType::$BOOL, true), ExpType::coerceToBool(new Token(ExpType::$FLOAT, 2.0)));
$this->assertEquals(new Token(ExpType::$BOOL, false), ExpType::coerceToBool(new Token(ExpType::$FLOAT, 0.0)));
$this->assertEquals(new Token(ExpType::$BOOL, false), ExpType::coerceToBool(new Token(ExpType::$NULL, null)));
// coerce null
$this->assertEquals($this->tokens['null'], ExpType::coerceToNull($this->tokens['null']));
$this->assertEquals($this->tokens['null'], ExpType::coerceToNull(new Token(ExpType::$RAW, 'null')));
}
public static function parse($tokenStream, $dataContext)
{
$scopes = array();
$expression = new PrimitiveExp(new Token('final'));
while ($token = array_shift($tokenStream)) {
// split non-primitive expression into primitive ones
switch ($token->type) {
case ExpType::$PAREN:
switch ($token->value) {
case '[':
$expression->append(new Token(ExpType::$DOT, '.'));
// drop through
// drop through
case '(':
ExpParser::scopePush($expression, $scopes, $token);
break;
case ']':
if ($expression->reason->value != '[') {
throw new ExpParserException("Unbalanced [], should be detected in Lexer");
}
ExpParser::scopePop($expression, $scopes, $dataContext);
break;
case ')':
if ($expression->reason->value != '(') {
throw new ExpParserException("Unbalanced (), should be detected in Lexer");
}
ExpParser::scopePop($expression, $scopes, $dataContext);
// close if it's a function
if ($expression->reason->type == ExpType::$FUNCTION) {
ExpParser::scopePop($expression, $scopes, $dataContext);
}
break;
default:
throw new ExpParserException("Token error: " . print_r($token, true));
}
break;
case ExpType::$FUNCTION:
ExpParser::scopePush($expression, $scopes, $token);
break;
case ExpType::$TERNARY:
if ($token->value != '?') {
throw new ExpParserException("Ternary token error");
}
$nextTernary = ExpParser::findNextTernary($tokenStream, 1);
$indicator = ExpType::coerceToBool($expression->evaluate($dataContext));
if ($indicator->value) {
// parsed?todo:skip
$nextCloseSymbol = ExpParser::findNextCloseSymbol($tokenStream, $nextTernary + 1);
array_splice($tokenStream, $nextTernary, $nextCloseSymbol - $nextTernary);
} else {
// parsed?skip:todo
$tokenStream = array_slice($tokenStream, $nextTernary + 1);
}
$expression = new PrimitiveExp($expression->reason);
break;
case ExpType::$COMMA:
if ($expression->reason->value != '(') {
throw new ExpParserException("Unbalanced (), should be detected in Lexer");
}
ExpParser::scopePop($expression, $scopes, $dataContext);
ExpParser::scopePush($expression, $scopes, new Token(ExpType::$PAREN, '('));
break;
default:
$expression->append($token);
}
}
if ($expression->reason->type != 'final') {
throw new ExpParserException("Gramma error on the non-primitive expression");
}
return $expression->evaluate($dataContext);
}
